Laser irradiation method and laser irradiation device and method of manufacturing semiconductor device

ABSTRACT

The present invention is characterized in that by laser beam being slantly incident to the convex lens, an aberration such as astigmatism or the like is occurred, and the shape of the laser beam is made linear on the irradiation surface or in its neighborhood. Since the present invention has a very simple configuration, the optical adjustment is easier, and the device becomes compact in size. Furthermore, since the beam is slantly incident with respect to the irradiated body, the return beam can be prevented.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a laser irradiation method and alaser irradiation apparatus for using the method (apparatus including alaser and an optical system for guiding laser beam emitted from thelaser to an object to be irradiated). In addition, the present inventionrelates to a method of manufacturing a semiconductor device, whichincludes a laser beam irradiation step. Note that a semiconductor devicedescribed here includes an electro-optical device such as a liquidcrystal display device or a light emitting device and an electronicdevice which includes the electro-optical device as a part.

[0003] 2. Description of the Related Art

[0004] In recent years, a wide study has been made on a technique inwhich laser annealing is performed for a semiconductor film formed on aninsulating substrate made of glass or the like, to crystallize the film,to improve its crystallinity so that a crystalline semiconductor film isobtained, or to activate an impurity element. Note that a crystallinesemiconductor film in this specification indicates a semiconductor filmin which a crystallized region is present, and also includes asemiconductor film which is crystallized as a whole.

[0005] A method of forming pulse laser beam from an excimer laser or thelike by an optical system such that it becomes a square spot of severalcm or a linear shape of 100 mm or more in length on a surface to beirradiated, and scanning the laser beam (or relatively shifting anirradiation position of the laser beam with respect to the surface to beirradiated) to conduct annealing is superior in mass productivity and isexcellent in technology. The “linear shape” described here means not a“line” in the strict sense but a rectangle (or a prolate ellipsoidshape) having a high aspect ratio. For example, it indicates a shapehaving an aspect ratio of 2 or more (preferably, 10 to 10000). Note thatthe linear shape is used to obtain an energy density required forsufficiently annealing an object to be irradiated.

[0006]FIG. 7 shows an example of a configuration of an optical systemfor forming laser beam in a linear shape on a surface to be irradiated.This configuration is extremely general. All optical systems describedabove are based on the configuration shown in FIG. 7. According to theconfiguration, a cross sectional shape of laser beam is converted into alinear shape, and simultaneously an energy density distribution of laserbeam on the surface to be irradiated is homogenized. In general, anoptical system for homogenizing the energy density distribution of laserbeam is called a beam homogenizer.

[0007] Laser beam emitted from a laser 71 is divided in a directionperpendicular to a traveling direction thereof by a cylindrical lensgroup 73, thereby determining a length of linear laser beam in aperpendicular direction. The direction is called a first direction inthis specification. It is assumed that, when a mirror is inserted in acourse of an optical system, the first direction is changed inaccordance with a direction of light bent by the mirror. In theconfiguration, the cylindrical lens array is divided into seven parts.Then, the laser beams are synthesized on a surface to be irradiated 79by a cylindrical lens 74, thereby homogenizing an energy densitydistribution of the linear laser beam in the longitudinal direction.

[0008] Next, the configuration shown in the side view of FIG. 7 will bedescribed. Laser beam emitted from a laser 71 is divided in a directionperpendicular to a traveling direction thereof and the first directionby cylindrical lens arrays 72 a and 72 b, thereby determining a lengthof linear laser beam in a width direction. The direction is called asecond direction in this specification. It is assumed that, when amirror is inserted in a course of an optical system, the seconddirection is changed in accordance with a direction of light bent by themirror. In this configuration, the cylindrical lens arrays 72 a and 72 beach are divided into four parts. The divided laser beams aretemporarily synthesized by a cylindrical lens 74. After that, the laserbeams are reflected by a mirror 77 and then condensed by a doubletcylindrical lens 78 so that they become again single laser beam on thesurface to be irradiated 79. The doublet cylindrical lens 78 is a lenscomposed of two cylindrical lenses. Thus, a homogenized energy densitydistribution of the linear laser beam in a width direction and a lengthof the linear laser beam in a width direction are determined.

[0009] For example, an excimer laser in which a size in a laser windowis 10 mm×30 mm (which each are a half-width in beam profile) is used asthe laser 71 and laser beam is produced by the optical system having theconfiguration shown in FIGS. 7A and 7B. Then, linear laser beam whichhas a uniform energy density distribution and a size of 125 mm×0.4 mmcan be obtained on the surface to be irradiated 79.

[0010] At this time, when, for example, quartz is used for all basematerials of the optical system, high transmittance is obtained. Notethat coating is preferably conducted for the optical system such thattransmittance of 99% or more is obtained at a frequency of the usedexcimer laser.

[0011] Then, the linear laser beam formed by the above configuration isirradiated with an overlap state while being gradually shifted in awidth direction thereof. Thus, when laser annealing is performed for theentire surface of an amorphous semiconductor film, the amorphoussemiconductor film can be crystallized, crystallinity can be improved toobtain a crystalline semiconductor film, or an impurity element can beactivated.

SUMMARY OF THE INVENTION

[0012] However, as shown in FIG. 7, an optical system for forming alinear beam is complicated. There are problems that it is very difficultto perform optical adjustment to such an optical system, and inaddition, since the footprint becomes larger, the device is enlarged.

[0013] Furthermore, in the case where a laser beam whose reflectancewith respect to the irradiated body is high is used, when the foregoinglaser beam is perpendicularly incident into the irradiated body, what iscalled a return beam is generated, which returns on the same opticalpath when the beam is incident into the irradiated body. The return beambecomes a factor having a bad influence on an output of the laser andthe variation of frequencies and the destruction of the rod or the like.

[0014] Hence, an object of the present invention is to provide a laserirradiation device in which a linear beam is formed using an opticalsystem more simplified than the conventional ones and which caneffectively anneal using such a linear beam, and a laser irradiationmethod using such a laser irradiation device. Moreover, another objectof the present invention is to provide a method of manufacturing asemiconductor device in which the foregoing laser irradiation method isincluded in its step.

[0015] The present invention is characterized in that an aberration suchas an astigmatism or the like is generated by a laser beam being slantlyincident with respect to the convex lens, and the shape of the laserbeam on the irradiation surface or in its neighborhood is made in alinear.

[0016] The configuration of the invention relating to a laserirradiation device disclosed in the present specification ischaracterized in that it has a laser and a convex lens slantly set withrespect to the traveling direction of the laser beam emitted from theforegoing laser and making the shape of the foregoing laser beam linearon the irradiation surface or in its neighborhood.

[0017] Moreover, as for the other configuration of the inventionrelating to a laser irradiation device, it is a laser irradiation devicehaving a laser and a convex lens which is slantly set to the travelingdirection of the laser beam emitted from the foregoing laser and makesthe shape of the foregoing laser beam on the irradiation surface or inits neighborhood in a linear shape, it is characterized as follows:supposing that the beam width measured when a laser beam emitted fromthe laser via the foregoing convex lens is incident into the irradiatedbody formed on the substrate is w, and the thickness of the foregoingsubstrate is d, the foregoing laser beam is incident with respect to theforegoing irradiated body, at an incident angle θ satisfying thefollowing expression:

θ≧arc tan(w/(2×d))

[0018] In the respective configurations described above, the foregoinglaser is characterized in that it is a solid state laser, a gas laser,or a metal laser of continuous oscillation or pulse oscillation. Itshould be noted that as the foregoing solid state laser, YAG laser, YVO₄laser, YLF laser, YAlO₃ laser, glass laser, ruby laser, alexandritelaser, Ti: sapphire laser or the like of continuous oscillation or pulseoscillation are listed, as the foregoing gas laser, excimer laser, Arlaser, Kr laser, CO₂ laser or the like of continuous oscillation orpulse oscillation are listed, and as the foregoing metal laser,helium-cadmium laser, copper vapor laser, gold vapor laser and the likeare listed.

[0019] Moreover, in the respective configurations described above, it isdesirable that the foregoing laser beam has been converted into a higherharmonic wave by a non-linear optical element. For example, it is knownthat a YAG laser emits a laser beam in the wavelength of 1065 nm as afundamental wave. The absorption coefficient of this laser beam withrespect to the silicon film is very low, so it is difficult from thetechnical viewpoint to crystallize an amorphous silicon film which isone of semiconductor films if it remains as it is. However, this laserbeam can be converted into a shorter wavelength using a nonlinearoptical element, and as a higher harmonic wave, the second higherharmonic wave (532 nm), the third higher harmonic wave (355 nm), thefourth higher harmonic wave (266 nm) and the fifth harmonic wave (213nm) are listed. Since these higher harmonic waves have high absorptioncoefficients with respect to the amorphous silicon film, these can beutilized for crystallization of the amorphous silicon film.

[0020] Moreover, in the respective configurations described above, theforegoing convex lens is characterized in that it is an aspherical lens.Furthermore, as a convex lens, meniscus lens, biconvex lens,plano-convex lens and the like are listed, however, as the convex lensin the present invention, it may be any lens out of these lenses and theincident surface of the laser beam may be either of the two surfaces ofthe convex lens.

[0021] Moreover, in the configurations described above, for theforegoing substrate, a glass substrate, a quartz substrate, a siliconsubstrate, a plastic substrate, a metal substrate, a stainless cladsubstrate, a flexible substrate and the like can be utilized. As theforegoing glass substrate, a substrate consisted of glass such as bariumborosilicate glass, aluminoborosilicate glass or the like can be listed.Moreover, a flexible substrate is referred to a substrate in a filmshape consisted of PET, PES, PEN, acryl or the like, if a semiconductordevice is prepared by utilizing the flexible substrate, the weightlightening of it is expected. If on the surface or on the surface andthe back surface of the flexible substrate, a barrier layer made ofaluminum film (AlON, AlN, AlO or the like), carbon film (DLC (diamondlike carbon) or the like), SiN or the like is formed in a monolayer ormultilayer, it is desirable that the durability or the like is enhanced.

[0022] Moreover, the configuration of the invention relating to a laserirradiation method disclosed in the present specification ischaracterized in that through a convex lens slantly set with respect tothe traveling direction of the laser beam, a linear beam is formed onthe irradiation surface or in its neighborhood, the foregoing linearbeam irradiates while the foregoing linear beam is relatively moved withrespect to the irradiated body. Moreover, the other configuration of theinvention relating to a laser irradiation method is characterized inthat, through a convex lens slantly set with respect to the travelingdirection of the laser beam, a linear beam is formed on the irradiationsurface or in its neighborhood. Supposing that a beam width measuredwhen the foregoing linear beam is incident into the irradiated bodyformed on the substrate is w, and the thickness of the foregoingsubstrate is d, the foregoing linear beam is incident into theirradiated body, at the incident angle θ satisfying the followingexpression:

θ≧arc tan(w/(2×d))

[0023] and the foregoing linear beam irradiates while the foregoinglinear beam is moved relatively to the foregoing irradiated body. In therespective configurations described above, the foregoing laser ischaracterized in that it is a solid state laser, a gas laser, or a metallaser of continuous oscillation or pulse oscillation. It should be notedthat as the foregoing solid state laser, YAG laser, YVO₄ laser, YLFlaser, YAlO₃ laser, glass laser, ruby laser, alexandrite laser, Ti:sapphire laser or the like of continuous oscillation or pulseoscillation are listed, as the foregoing gas laser, excimer laser, Arlaser, Kr laser, CO₂ laser or the like of continuous oscillation orpulse oscillation are listed, and as the foregoing metal laser,helium-cadmium laser, copper vapor laser, gold vapor laser and the likeare listed. Moreover, in the respective configurations described above,it is desirable that the foregoing laser beam has been converted into ahigher harmonic wave by a non-linear optical element. Moreover, in therespective configurations described above, the foregoing convex lens ischaracterized in that it is an aspherical lens. Furthermore, as a convexlens, meniscus lens, biconvex lens, plano-convex lens and the like arelisted, however, as the convex lens in the present invention, it may beany lens out of these lenses and the incident surface of the laser beammay be either of the two surfaces of the convex lens.

[0024] Moreover, in the configurations described above, for theforegoing substrate, a glass substrate, a quartz substrate, a siliconsubstrate, a plastic substrate, a metal substrate, a stainless cladsubstrate, a flexible substrate and the like can be utilized.

[0025] Moreover, the configuration of the invention relating to a methodof manufacturing a semiconductor device disclosed in the presentspecification is characterized in that through a convex lens slantly setwith respect to the traveling direction of the laser beam, a linear beamis formed on the irradiation surface or in its neighborhood, theforegoing linear beam irradiates while the foregoing linear beam isrelatively moved with respect to the semiconductor film.

[0026] Moreover, the other configuration of the invention relating to amethod of manufacturing a semiconductor device is characterized in that,through a convex lens slantly set with respect to the travelingdirection of the laser beam, a linear beam is formed on the irradiationsurface or in its neighborhood. Supposing that a beam width measuredwhen the foregoing linear beam is incident into the semiconductor filmformed on the substrate is w, and the thickness of the foregoingsubstrate is d, the foregoing linear beam is incident with respect tothe semiconductor film at the incident angle 0 satisfying the followingexpression:

θ≧arc tan(w/(2×d))

[0027] and the foregoing linear beam irradiates while the foregoinglinear beam is moved relatively to the foregoing semiconductor film. Inthe respective configurations described above, the foregoing laser ischaracterized in that it is a solid state laser, a gas laser, or a metallaser of continuous oscillation or pulse oscillation. It should be notedthat as the foregoing solid state laser, YAG laser, YVO₄ laser, YLFlaser, YAlO₃ laser, glass laser, ruby laser, alexandrite laser, Ti:sapphire laser or the like of continuous oscillation or pulseoscillation are listed, as the foregoing gas laser, excimer laser, Arlaser, Kr laser, CO₂ laser or the like of continuous oscillation orpulse oscillation are listed, and as the foregoing metal laser,helium-cadmium laser, copper vapor laser, gold vapor laser and the likeare listed. Moreover, in the respective configurations described above,it is desirable that the foregoing laser beam has been converted into ahigher harmonic wave by a non-linear optical element. Moreover, in therespective configurations described above, the foregoing convex lens ischaracterized in that it is an aspherical lens. Furthermore, as a convexlens, meniscus lens, biconvex lens, plano-convex lens and the like arelisted, however, as the convex lens in the present invention, it may beany lens out of these lenses and the incident surface of the laser beammay be either of the two surfaces of the convex lens.

[0028] Moreover, in the configurations described above, for theforegoing substrate, a glass substrate, a quartz substrate, a siliconsubstrate, a plastic substrate, a metal substrate, a stainless cladsubstrate, a flexible substrate and the like can be utilized.

[0029] Moreover, in the respective configurations, it is desirable thatthe foregoing semiconductor film is a film containing silicon. Since thepresent invention has a very simplified configuration, opticaladjustment is easy, and the device becomes compact in size. Moreover,even in the case where the irradiation is performed using a plurality oflaser beams, since the optical system is simplified, it is possible toeasily make the same shape of the all laser beams. In order to performthe uniform annealing, it is very important to make the same shape ofplurality of laser beams. If the beam irradiates on a substrate having alarge area using such a plurality of laser beams, it is capable ofenhancing the throughput. Moreover, the beam can be utilized bysynthesizing such a plurality of lasers. Furthermore, since the presentinvention is slantly incident with respect to the irradiated body, thereturn beam can be prevented, since an isolator is not required to set,the configuration becomes more simplified. Therefore, the reduction ofthe cost can be realized. Moreover, the efficient irradiation can beperformed with respect to the semiconductor film formed on thesubstrate, and it makes possible that the variation of the electricalproperty of TFT prepared can be reduced using such a semiconductor.Then, the operating property and reliability of semiconductor preparedfrom such a TFT can be also enhanced.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In the a accompanying drawings:

[0031]FIG. 1 is a diagram for showing an example of an optical system ofthe present invention;

[0032]FIG. 2 is a diagram for obtaining an incident angle θ of a laserbeam with respect to an object to be irradiated;

[0033]FIG. 3 is a diagram showing an example of a shape of a laser beamformed on an irradiation surface according to the present invention;

[0034]FIG. 4 is a diagram showing an example of an optical system of thepresent invention in the case a plurality of laser beams is used;

[0035]FIG. 5 is a diagram showing an example of an optical system of thepresent invention in the case a plurality of laser beams is used;

[0036]FIG. 6 is a diagram showing an example of an optical system of thepresent invention in the case a plurality of laser beams is used;

[0037]FIG. 7 is a diagram showing an example of a conventional opticalsystem;

[0038]FIGS. 8A to 8C are cross sectional views for explaining steps ofmanufacturing a pixel TFT and a TFT for a driver circuit;

[0039]FIGS. 9A to 9C are cross sectional views for explaining steps ofmanufacturing a pixel TFT and a TFT for a driver circuit;

[0040]FIG. 10 is a cross sectional view for explaining a step ofmanufacturing a pixel TFT and a TFT for a driver circuit;

[0041]FIG. 11 is a top view for explaining a structure of a pixel TFT;

[0042]FIG. 12 is a cross sectional view of an active matrix type liquidcrystal display device;

[0043]FIG. 13 is a cross sectional structure diagram of a driver circuitand pixel portion of a light emitting device;

[0044]FIGS. 14A to 14F are diagrams showing examples of a semiconductordevice;

[0045]FIGS. 15A to 15D are diagrams showing examples of a semiconductordevice;

[0046]FIGS. 16A to 16C are diagrams showing examples of a semiconductordevice;

[0047]FIG. 17 is a diagram showing an example of performing acrystallization of a semiconductor film by using the present inventionand observing the semiconductor film by SEM;

[0048]FIG. 18 is a diagram showing an example of performing acrystallization of a semiconductor film by using the present inventionand observing the semiconductor film by SEM;

[0049]FIGS. 19A to 19H are diagrams showing examples of manufacturingTFTs by using the present invention;

[0050]FIGS. 20A to 20B are diagrams showing examples of manufacturingTFT by using the present invention and measuring the electriccharacteristics;

[0051]FIGS. 21A to 21C are diagrams showing examples of manufacturingTFT by using the present invention;

[0052]FIGS. 22A to 22B are diagrams showing examples of manufacturingTFT by using the present invention and measuring the electriccharacteristics;

[0053]FIGS. 23A to 23B are diagrams showing examples of manufacturingTFT by using the present invention and measuring the electriccharacteristics; and

[0054]FIG. 24 is a diagram showing an example of an optical system ofthe present invention.

[0055]FIGS. 25A to 25C are graphs showing ID-VG characteristic of a TFTmanufactured by combining laser beam irradiation with thermalcrystallization using nickel having catalytic function in thecrystallization and shows dependency on channel length.

[0056]FIGS. 26A to 26C are graphs showing ID-VG characteristic of a TFTmanufactured by laser beam irradiation in the crystallization and showsdependency on channel length.

[0057]FIG. 27 is graphs showing ID-VG characteristic of a TFT with afilm thickness of 66 nm in complete depression type.

[0058]FIG. 28 is graphs showing ID-VG characteristic of a TFT with afilm thickness of 150 nm in partial depletion type.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0059] Embodiment Mode

[0060] In the present Embodiment Mode, a method of forming a linear beamwill be described below with reference to FIG. 1 and FIG. 2.

[0061] A laser beam emitted from a laser 101 is incident into a convexlens 103 via a mirror 102. Here, as the laser 101, a solid state laser,a gas laser or a metal laser of continuous oscillation or pulseoscillation is used. It should be noted that as the foregoing solidstate laser, YAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glass laser,ruby laser, alexandrite laser, Ti: sapphire laser and the like arelisted, as the foregoing gas laser, excimer laser, Ar laser, Kr laser,CO₂ laser and the like of continuous oscillation or pulse oscillationare listed, and as the foregoing metal laser, helium-cadmium laser,copper vapor laser, gold vapor laser and the like are listed. Then, alaser oscillated from the laser 101 may be converted into a higherharmonic wave by a non-linear optical element. Moreover, a beam expanderbetween the laser 101 and the mirror 102 or between the mirror 102 andthe convex lens 103 is set and may be expanded into the desired size inboth of longer direction and shorter direction, respectively. The beamexpander is particularly effective in the case where the shape of thelaser beam emitted from the laser is small. Moreover, the mirror may notbe set, or a plurality of the mirrors may be set.

[0062] The laser beam is made slantly incident with respect to theconvex lens 103. The focal position is shifted with aberration such asastigmatism by being incident in such a way, a linear beam 106 can beformed on the irradiation surface or in its neighborhood. It should benoted that if the convex lens 103 is made of a synthetic quartz glass,it is desired since a high transparency is obtained. Moreover, as forthe coating provided on the surface of the convex lens 103, it isdesirable that one capable of obtaining the transparency of 99% or morewith respect to the wavelength of the utilized laser beam is used.Moreover, as for the convex lens, it is desirable that an asphericallens whose spherical lens aberration is corrected is used. If anaspherical lens is used, the condensing property is enhanced, and theaspect ratio and the distribution of the energy density are alsoenhanced.

[0063] Then, while the linear beam 106 formed thus irradiates, forexample, it can irradiate the desired region or whole area on theirradiated body 104 by being relatively moved with respect to theirradiated body 104, for example, in the direction indicated with thereference numeral 107 or the directions indicated with the referencenumerals 108, 109. “To be relatively moved” is concretely referred to“to operate the irradiated body disposed on the stage”.

[0064] However, depending on the wavelength of a laser beam, theinterference may arise between the reflection beam on the surface of theirradiated body 104 and the reflection beam on the back surface of thesubstrate 105 on which the irradiated body 104 is formed. In FIG. 2, asthe irradiated body 104, an example in which a semiconductor 11 isformed on a substrate 10 is shown. If the reflection beam 14 on thesurface of the semiconductor film 11 and the reflection beam 13 on theback surface of the substrate 10 are not superimposed, the interferencedue to these beams does not occur.

[0065] In this case, when a flat plane which is perpendicular to theirradiated surface and which is one of the plane containing short sideor the long side of a rectangle which is assumed to be a shape of thelong beam is defined as incident surface, it is desired that theincident angle θ of the laser beam satisfies θ≧arctan (W/2d) where W isa length of the short side or the long side contained in the incidentsurface, and the thickness of the substrate having transparency withrespect to the laser beam is d. This W is W=(W₁+W₂)/2 when W₁ is a beamlength 15 of a laser beam incident on the irradiated surface, and W₂ isa beam length of a laser beam reflected from a back surface of thesubstrate 10. It is to be noted that when the locus of the laser beam isnot present on the incident surface, an incident angle of a projectedone of the locus on the incident surface is defined as θ. If the laserbeam is incident at the incident angle θ, the reflected beam on thesurface of the substrate is not interfered with the reflected beam fromthe back surface of the substrate to enable the irradiation of the laserbeam to be conducted uniformly. Further, by setting the incident angle θon the irradiated body to the Brewster's angle, the reflectivity isminimized to enable the laser beam to be used effectively. In the above,refractive index of the substrate is 1. In practice, the refractiveindex of many substrates is about 1.5. When this value is taken intoconsideration, a calculation value larger than the angle calculated inthe above is obtained. However, because energies of both sides of thelengthwise direction of the linear beam are attenuated, interferenceinfluence is small in this part and sufficient interference attenuationeffect is obtained with the above calculated value.

[0066] Moreover, the reflection prevention film may be formed on thesurface of the irradiated body.

[0067] When the annealing of the semiconductor film is performed usingsuch a laser irradiation device, the relevant semiconductor film can becrystallized, the crystalline semiconductor can be obtained by enhancingthe crystallinity and the activation of the impurity elements can becarried out.

[0068] It should be noted that the shapes of the laser beams aredifferent depending on the kinds of the laser beams emitted from thelasers, even if the laser beam is formed by the optical system, it issusceptible to and easily influenced with the original shape. Forexample, the shape of the laser beam emitted from a XeCl excimer laseris in a rectangular shape, as for the shape of the laser beam emittedfrom the solid state laser, if the rod shape is in a cylinder shape, itbecomes a circular shape, and if it is in a slab shape, it becomes arectangular shape. The present invention can be applied to any shape.

[0069] The present invention comprising the configurations describedabove will be described further in detail by Embodiments indicatedbelow.

[0070] Embodiments

[0071] Embodiment 1

[0072] In the present Embodiment, an example in which a linear beam isformed by the present invention will be described below with referenceto FIG. 1 and FIG. 3.

[0073] As the laser 101, YAG laser is used. Supposing that the laserbeam oscillated from the laser 101 is converted to the second higherharmonic wave by a non-linear optical element contained in the laser101. At this time, supposing that the laser beam is in TEMoo mode, andhas 2.25 mm of beam diameter and 0.35 mrad of spreading angle.

[0074] Subsequently, the beam is incident with respect to the convexlens 103 having a focal length of 20 mm at the incident angle φ of 20degrees. Then, in the present Embodiment, the simulation is performed onthe shape of the laser beam formed on the irradiation surface disposedin parallel with the convex lens. The results of these are shown in FIG.3. From FIG. 3, it is understood that a linear beam having a length of420 μm and a width of 40 μm is formed on the irradiation surface.Moreover, the distribution of the energy density of the linear beam is aGaussian distribution.

[0075] From the results of this simulation, it can be confirmed that alinear beam is formed on the irradiation surface or in its neighborhoodaccording to the present invention. Then, when the annealing of asemiconductor film is performed using such a laser irradiation device,the relevant semiconductor film can be crystallized, a crystallinesemiconductor film can be obtained by enhancing the crystallinity, andthe activation of the impurity can be carried out.

[0076] Embodiment 2

[0077] In the present Embodiment, an example in which the irradiation ofthe laser beam is performed using a plurality of laser beams will bedescribed below with reference to FIG. 4. As lasers 111 a-111 c, YAGlasers are used, these are converted into the second higher harmonicwave by a non-linear optical element. Then, after the respective laserbeams emitted from the lasers 111 a-111 c travel via mirrors 112 a-112c, these are slantly incident with respect to the convex lenses 113a-113 c. By slantly being incident, the focal position is shifted by anaberration such as astigmatism or the like, a linear beam can be formedon the irradiation surface or in its neighborhood. Moreover, it isdesirable that an aspherical lens is used for the convex lens. It shouldbe noted that abeam expander between the lasers 111 a-111 c and themirrors 112 a-112 c or between the mirrors 112 a-112 c and the convexlenses 113 a-113 c is set and may be expanded into the desired sizes inboth of longer direction and shorter direction, respectively. Moreover,the mirror may not be set, or a plurality of the mirrors may be set.

[0078] Then, while the linear beam formed in this way irradiates, it canirradiate the desired region or whole area on the irradiated body 104 bybeing relatively moved with respect to the irradiated body 104, forexample, in the direction indicated with the reference numeral 107 orthe directions indicated with the reference numerals 108, 109.

[0079] Since in the present invention, the optical system for formingthe linear beam has a very simple configuration, it is easy to make aplurality of laser beams linear beams having the same shape on theirradiation surface. Therefore, since the same annealing is carried outon any irradiation surface where any linear beam irradiates, the wholesurface of the irradiated body reaches to have a uniform physicalproperty and the throughput is enhanced.

[0080] It should be noted that in the present invention, although anexample in which three beams of lasers are used is exemplified, thenumber of lasers is not limited to this, and the same kind of laser maybe not used. For example, it is also possible that a plurality ofdifferent lasers are employed, the desired region is irradiated by thedesired laser, semiconductor films having different physical propertiesare formed and TFTs having different properties are prepared on the samesubstrate.

[0081] Embodiment 3

[0082] In the present Embodiment, an example in which the irradiation ofthe laser beams are carried out from both sides of the irradiated bodyusing a plurality of lasers will be described below with reference toFIG. 5.

[0083] As lasers 121 a, 121 b, YVO₄ lasers of continuous oscillation areused, these are converted into the second higher harmonic wave byutilizing a non-linear optical element. Then, after the respective laserbeams emitted from the lasers 121 a,121 b travel via mirrors 122 a,122b, these are slantly incident with respect to the convex lenses 123a,123 b. By slantly being incident, the focal position is shifted by anaberration such as astigmatism or the like, a linear beam can be formedon the irradiation surface or in its neighborhood. Moreover, it isdesirable that an aspherical lens is used for the convex lens.

[0084] It should be noted that a beam expander between the lasers 121 a,121 b and the mirrors 122 a, 122 b or between the mirrors 122 a, 122 band the convex lenses 123 a, 123 b is set and may be expanded into thedesired sizes in both of longer direction and shorter direction,respectively. Moreover, the mirror may not be set, or a plurality of themirrors may be set.

[0085] Then, while the linear beam formed in this way irradiates, it canirradiate the desired region or whole area on the irradiated body 104 bybeing relatively moved with respect to the irradiated body 104, forexample, in the direction indicated with the reference numeral 107 orthe directions indicated with the reference numerals 108, 109.

[0086] Since in the present invention, the optical system for formingthe linear beam has a very simple configuration, it is easy to make aplurality of laser beams linear beams having the same shape on theirradiation surface. Therefore, a plurality of linear beams can beeasily superimposed each other. Even in the case where a laser having alower output is used depending on the irradiated body, it can besufficiently applied according to the present Embodiment.

[0087] It should be noted that in the present invention, although anexample in which two beams of lasers are used is exemplified, the numberof lasers is not limited to this, and the different kinds of lasers maybe used.

[0088] Moreover, it is capable of being carried out that the presentEmbodiment is combined with Embodiment 2.

[0089] Embodiment 4

[0090] In the present Embodiment, an example in which the irradiation ofthe laser beams is carried out by utilizing a plurality of lasers andsuperimposing these on the surface of the irradiated body will bedescribed below with reference to FIG. 6.

[0091] As lasers 131 a, 131 b, YLF lasers of continuous oscillation areused, these are converted into the third higher harmonic wave byutilizing a non-linear optical element. Then, after the respective laserbeams emitted from the lasers 131 a, 131 b are slantly incident withrespect to the convex lenses 133 a, 133 b. By slantly being incident,the focal position is shifted by an aberration such as astigmatism orthe like, a linear beam can be formed on the irradiation surface or inits neighborhood. Moreover, it is desirable that an aspherical lens isused for the convex lens.

[0092] It should be noted that beam expanders between the lasers 131 a,131 b and the convex lenses 133 a, 133 b are set and may be expandedinto the desired sizes in both of longer direction and shorterdirection, respectively. Moreover, the mirror may not be set, or aplurality of the mirrors may be set. Then, while the linear beam formedin this way irradiates, it can irradiate the desired region or wholearea on the irradiated body 104 by being relatively moved with respectto the irradiated body 104, for example, in the direction indicated withthe reference numeral 107 or the directions indicated with the referencenumerals 108, 109.

[0093] Since in the present invention, the optical system for formingthe linear beam has a very simple configuration, it is easy to make aplurality of laser beams linear beams having the same shape on theirradiation surface. Therefore, a plurality of linear beams can beeasily superimposed each other. Even in the case where a laser having alower output is used depending on the irradiated body, it is capable ofbeing sufficiently applied according to the present Embodiment.

[0094] It should be noted that in the present invention, although anexample in which two beams of lasers are used is exemplified, the numberof lasers is not limited to this, and the different kinds of lasers maybe used. Moreover, although laser beams are synthesized on theirradiation surface, after being synthesized, a linear beam may beformed by an optical system.

[0095] Moreover, it is possible that the present Embodiment is freelycombined with Embodiment 2 or Embodiment 3.

[0096] Embodiment 5

[0097] A method of manufacturing an active matrix substrate is explainedin this embodiment using FIGS. 8 to 11. A substrate on which a CMOScircuit, a driver circuit, and a pixel portion having a TFT pixel and aholding capacity are formed together is called active matrix substratefor convenience.

[0098] First, a substrate 400 made from glass such as bariumborosilicate glass or aluminum borosilicate glass is used in thisembodiment. Note that substrates such as quartz substrates, siliconsubstrates, metallic substrates, and stainless steel substrates havingan insulating film formed on the substrate surface may also be used asthe substrate 400. Further, a plastic substrate having heat resistingproperties capable of enduring the processing temperatures used in thisembodiment may also be used. Because this invention can easily form alinear beam with a uniform energy distribution, it is possible thatannealing the large area substrate is conducted effectively by using aplurality of linear beams.

[0099] Next, a base film 401 made from an insulating film such as asilicon oxide film, a silicon nitride film, or a silicon oxynitride filmis then formed on the substrate 400 by the known method. A two layerstructure is used as the base film 401 in this embodiment, but a singlelayer of the above-mentioned insulating film may also be used, and astructure in which more than two layers are laminated may also be used.

[0100] Next, semiconductor layers are formed on the base film. First ofall, semiconductor film is formed with a thickness of 25 to 200 nm(preferably 30 to 150 nm) by a known method (such as the sputteringmethod, the LPCVD method, and the plasma CVD method). Then, thesemiconductor film is crystallized by a laser crystallization method. Asthe laser crystallization method, the laser beam irradiates to thesemiconductor film by applying one of Embodiments 1 to 4 or by freelycombining any one of Embodiments 1 to 4. It is preferable that asolid-state laser of continuous oscillation or pulse oscillation, a gaslaser, or metallic laser is used. Note that, as the solid-state laser,there may be given a YAG laser, a YVO₄ laser, a YLF laser, a YAlO₃laser, a glass laser, a ruby laser, an alexandrite laser, a Ti:sapphirelaser, and the like. As a the gas laser, there may be given a excimerlaser of continuous oscillation or pulse oscillation, Ar laser, Krlaser, CO₂ laser, or the like. And as the metallic laser, there may begiven a helium cadmium laser, a copper vapor laser, or a gold vaporlaser. Of course, not only the laser crystallization method but also anyother known crystallization method (RTA, the thermal crystallizationmethod using a furnace annealing, the thermal crystallization methodusing metallic elements which promote crystallization) may also becombined. The semiconductor film may be an amorphous semiconductor film,a microcrystal semiconductor film or a crystalline semiconductor film.Alternatively, the semiconductor film may be a compound semiconductorfilm having an amorphous structure such as an amorphous silicongermanium film.

[0101] In this embodiment, plasma CVD method is used to form anamorphous silicon film with a thickness of 50 nm, and then the thermalcrystallization method using metallic elements, which promotecrystallization, and laser crystallization method are used for theamorphous silicon film. Nickel is used as a metal element, and isintroduced onto the amorphous silicon film by a solution coating method.Then heat treatment is conducted at 500° C. for five hour, wherebyobtaining a first crystalline silicon film. Subsequently, the laser beamshot from a continuous oscillation YVO₄ laser with output 10 W isconverted into the second higher harmonic wave by a nonlinear opticalelement and then a linear laser beam is formed and irradiated by one ofthe optical system shown in Embodiments 1 thorough 4 or by the opticalsystem combined these embodiments, whereby obtaining a secondcrystalline silicon film. Irradiating the laser beam to the firstcrystalline silicon film, and changing the first crystalline siliconfilm to the second crystalline silicon film improve the crystallinity ofthe second crystalline silicon film. At this moment, about 0.01 to 100MW/cm² (preferably 0.1 to 10 MW/cm²) is necessary for the energydensity. The stage is relatively moved to the laser beam at a speed ofabout 0.5 to 2000 cm/s, and it irradiates, and then the crystallinesilicon film is formed. When the excimer laser of pulse oscillation isused, it is preferable that 300 Hz of frequency and 100 to 1000mj/cm²(typically, 200 to 800 mj /cm²) of laser energy density are used.At this moment, laser beam may be overlapped by 50 to 98%.

[0102] Of course, although a TFT can be formed by using the firstcrystalline silicon film, it is preferable that the second crystallinesilicon film is used to form the TFT since the second crystallinesilicon film has an improved crystallinity and electric characteristicsof TFT are improved. For instance, although, when TFT is formed by usingthe first crystalline silicon film, a mobility is almost 300 cm²/Vs,when TFT is formed by using the second crystalline silicon film, themobility is extremely improved with about 500 to 600 cm²/Vs.

[0103] The semiconductor layers 402 to 406 are formed by performingpatterning processing on thus obtained semiconductor film by using thephotolithography method.

[0104] Doping of a very small amount of an impurity element (boron orphosphorous) may be performed after forming the semiconductor layers 402to 406 in order to control a TFT threshold value.

[0105] A gate insulating film 407 is formed next, covering thesemiconductor layers 402 to 406. The gate insulating film 407 is formedby an insulating film containing silicon with a thickness of 40 to 150nm using plasma CVD or sputtering. In this embodiment, a siliconoxynitride film having a film thickness of 110 nm is formed by plasmaCVD method. The gate insulating film is of course not limited to asilicon oxynitride film, and other insulating films containing siliconmay be used in a single layer or in a lamination structure.

[0106] Further, if a silicon oxide film is used, it can be formed byplasma CVD method with a mixture of TEOS (Tetraethyl Orthosilicate) andO₂, at a reaction pressure of 40 Pa, with the substrate temperature setfrom 300 to 400° C., and by discharging at a high frequency (13.56 MHz)electric power density of 0.5 to 0.8 W/cm². Good characteristics as agate insulating film can be obtained by subsequently performing thermalannealing, at between 400 and 500° C., of the silicon oxide film thusmanufactured.

[0107] A first conductive film 408 having a film thickness of 20 to 100nm, and a second conductive film 409 having a film thickness of 100 to400 nm are then formed and laminated on the gate insulating film 407.The first conductive film 408, made from a TaN film having a filmthickness of 30 nm, and the second conductive film 409, made from a Wfilm having a film thickness of 370 nm, are formed and laminated in thisembodiment. The TaN film is formed by sputtering, and sputtering of a Tatarget is performed in a nitrogen atmosphere. Further, the W film isformed by sputtering using a W target. In addition, the W film can alsobe formed by thermal CVD method using tungsten hexafluoride (WF₆).Whichever is used, it is necessary to be able to make the film becomelow resistance in order to use it as a gate electrode, and it ispreferable that the resistivity of the W film be made less than 20 μΩcm.

[0108] Note that although the first conductive film 408 is TaN and thesecond conductive film 409 is W in this embodiment, there are noparticular limitations placed on the conductive films. The firstconductive film 408 and the second conductive film 409 may also beformed from an element selected from the group consisting of Ta, W, Ti,Mo, Al, Cu, Cr, and Nd, or from an alloy material having one of theseelements as its main constituent, or from a chemical compound of theseelements. Further, a semiconductor film, typically a polycrystallinecrystalline silicon film, into which an impurity element such asphosphorous is doped may also be used, as may an AgPdCu alloy.

[0109] Masks 410 to 415 are formed next from resist using aphotolithography method, and a first etching process is performed inorder to form electrodes and wirings. The first etching processing isperformed in accordance with first and second etching conditions (FIG.8B). An ICP (Inductively Coupled Plasma) etching method is used as afirst etching condition in this embodiment. A gas mixture of CF₄, Cl₂,and O₂ is used as an etching gas, the gas flow rates are set to 25:25:10(sccm), respectively, a plasma is generated by supplying a 500 W RF(13.56 MHz) electric power to a coil shape electrode at a pressure of 1Pa, and etching is performed. A 150 W RF (13.56 MHz) electric power isalso applied to the substrate side (sample stage), thereby applying asubstantially negative self-bias voltage. The W film is etched under thefirst etching conditions, and the edge portion of the first conductivelayer is made into a tapered shape.

[0110] The etching conditions are changed to a second etching conditionwithout removing the masks 410 to 415 made of resist. A gas mixture ofCF₄ and Cl₂ is used as an etching gas, the gas flow rates are set to30:30 (sccm), respectively, a plasma is generated by applying a 500 W RF(13.56 MHz) electric power to a coil shape electrode at a pressure of 1Pa, and etching is performed for approximately 30 seconds. A 20 W RF(13.56 MHz) electric power is also supplied to the substrate side(sample stage), thereby applying a substantially negative self-biasvoltage. The W film and the TaN film are both etched by on the sameorder by the second etching conditions using the gas mixture of CF₄ andCl₂. Note that the etching time may be increased on the order of 10 to20% in order to perform etching such that no residue remains on the gateinsulating film.

[0111] Edge portions of the first conductive layer and the secondconductive layer are made into a tapered shape in accordance with theeffect of a bias voltage, applied to the substrate side, by making theshapes of the resist masks suitable with the above-mentioned firstetching condition. The angle of the tapered portions is from 15 to 45°.First shape conductive layers 417 to 422 (first conductive layers 417 ato 422 a, and second conductive layers 417 b to 422 b) are thus formedfrom the first conductive layers and the second conductive layers by thefirst etching process. Reference numeral 416 denotes a gate insulatingfilm, and regions not covered by the first shape conductive layers 417to 422 become thinner by approximately 20 to 50 nm through etching.

[0112] A second etching process is then performed without removing themasks made of resist (FIG. 8C). Here, W film is selectively etched byusing CF₄, Cl₂, and O₂ for the etching gas. At this time, the secondconductive layers 428 b to 433 b are formed by the second etchingprocess. On the other hand, the first conductive layers 417 a to 422 aare hardly etched and the second shape conductive layers 428 to 433 areformed.

[0113] A first doping process is then performed without removing themasks made of resist and the semiconductor layer is added to theimpurity element which imparts n-type at a low concentration. The dopingprocess may be performed by ion doping method or ion injection method.Ion doping is performed with process conditions in which the dosage isset from 1×10¹³ to 5×10¹⁴/cm², and the acceleration voltage is setbetween 40 to 80 keV. Doping is performed in this embodiment with thedosage set to 1.5×10¹³/cm², and the acceleration voltage set to 60 keV.An element belonging to the group 15, typically phosphorous (P) orarsenic (As) is used as an impurity element which imparts n-type.Phosphorous (P) is used here. In this case the conductive layers 428 to433 act as masks with respect to the impurity element which impartsn-type conductivity, and the impurity regions 423 to 427 are formed in aself-aligning manner. The impurity element which imparts n-type is addedto the impurity regions 423 to 427 at a concentration in a range of1×10¹⁸ to 1×10²⁰/cm³.

[0114] Next, after removing the masks made of resist, new masks 434 a to434 c made of resist are formed, and the second doping process isperformed in higher acceleration voltage than the first doping process.Ion doping is performed with process conditions in which the dosage isset from 1×10¹³ to 1×10¹⁵/cm², and the acceleration voltage is setbetween 60 to 120 keV. The doping process is performed by using thesecond conductive layers 428 b to 432 b as masks and the semiconductorlayer under the tapered portion of the first conductive layer is addedto the impurity element. Continuously the acceleration voltage islowered than the second doping process, the third doping process isdone, and the state of FIG. 9A is obtained. Ion doping method isperformed with process conditions in which the dosage is set from 1×10¹⁵to 1×10¹⁷/cm², and the acceleration voltage is set between 50 to 100keV. Low concentration impurity regions 436, 442 and 448 overlappingwith the first conductive layer are added to the impurity element, whichimparts n-type within the range of the density of 1×10⁸ to 5×10¹⁹/cm² bythe second doping process and the third doping process and highconcentration impurity regions 435, 441, 444 and 447 are added to theimpurity element, which imparts n-type within the range of the densityof 1×10¹⁹ to 5×10²¹/cm².

[0115] Of course, the second doping process and the third doping processcan be one-time doping processes by making it to a suitable accelerationvoltage and it is also possible to form the low concentration impurityregion and high concentration impurity region.

[0116] Next, after removing the masks made of resist, new masks 450 a to450 c made from resist are formed and the fourth doping process isperformed. Impurity regions 453, 454, 459 and 460, to which an impurityelement which imparting a conductivity type opposite to that of theabove one conductivity type is added, are formed in accordance with thefourth doping process in the semiconductor films which become activelayers of the p-channel type TFTs. The second conductive layers 429 b to432 b are used as masks with respect to the impurity element, and animpurity element which imparts p-type conductivity is added to form theimpurity regions in a self-aligning manner. The impurity regions 453,454, 459 and 460 are formed by ion doping method using diborane (B₂H₆)in this embodiment (FIG. 9B). The semiconductor layers for forming then-channel type TFT are covered with the masks 450 a to 450 c made ofresist when the fourth doping process is performed. Phosphorous is addedat different concentrations into the impurity regions 439 and 447 by thefirst to third doping processes. However, by performing doping such thatthe concentration of the impurity element which imparts p-typeconductivity becomes from 1×10¹⁹ to 5×10²¹ atoms/cm³ in the respectiveregions, no problems develop in making the regions function as sourceregions and drain regions of the p-channel type TFT.

[0117] The impurity regions are thus formed in the respectivesemiconductor layers by the steps up through this point.

[0118] A first interlayer insulating film 461 is formed next afterremoving the masks 450 a to 450 c made of resist. This first interlayerinsulating film 461 is formed from an insulating film containingsilicon, having a thickness of 100 to 200 nm, by using plasma CVD methodor sputtering method. A silicon oxynitride film having a thickness of150 nm is formed by plasma CVD method in this embodiment. The firstinterlayer insulating film 461 is of course not limited to a siliconoxynitride film, and other insulating films containing silicon may alsobe used, as a single layer or a lamination structure.

[0119] Subsequently, a recovery of the crystallinity of thesemiconductor layer and an activation of the impurity elements added tothe respective semiconductor layers are performed by irradiating thelaser beam, as shown in FIG. 9C. As the laser activation, the laser beamirradiates to the semiconductor film by applying one of Embodiments 1 to4 or by freely combining with these embodiments. It is preferable that asolid-state laser of a continuous oscillation or a pulse oscillation, agas laser, or metallic laser is used. Note that, as the solid-statelaser, there may be given a YAG laser of a continuous oscillation or apulse oscillation, a YVO₄ laser, a YLF laser, a YAlO₃ laser, a glasslaser, a ruby laser, an alexandrite laser, a Ti: sapphire laser, and thelike. As a the gas laser, there may be given a excimer laser ofcontinuous oscillation or pulse oscillation, Ar laser, Kr laser, CO₂laser, or the like. And as the metallic laser, there may be given ahelium cadmium laser, a copper vapor laser, or a gold vapor laser. Atthis moment, if a continuous oscillation laser is used, about 0.01 to100 MW/cm² (preferably 0.1 to 10 MW/cm²) is necessary for the energydensity of laser beam. The substrate is relatively moved to the laserbeam at a speed of about 0.5 to 2000 cm/s. And, if a pulse oscillationlaser is used, it is preferable that 300 Hz of frequency and 50 to 1000mj/cm² (typically, 50 to 500 mj/cm²) of laser energy density are used.At this moment, laser beam may be overlapped by 50 to 98%. Besides laserannealing method, thermal annealing method or rapid thermal annealingmethod (RTA method) and the like can be applied.

[0120] Further, the activation may also be performed before theformation of a first interlayer insulating film. However, if the wiringmaterial used is weak with respect to heat, then it is preferable toperform the activation processing after forming an interlayer insulatingfilm (an insulating film having silicon as its main constituent, forexample a silicon nitride film) in order to protect the wirings and thelike, as in this embodiment.

[0121] Then, a heat treatment can also be performed (at 300 to 550° C.for 1 to 12 hours) and it is possible to conduct a hydrogenation. Thisprocess is one of terminating dangling bonds in the semiconductor layersby hydrogen contained within the first interlayer insulating film 461.The semiconductor layers can be hydrogenated whether or not the firstinterlayer insulating film exists. Plasma hydrogenation (using hydrogenexcited by a plasma), and a heat treatment for 1 to 12 hours at atemperature of 300 to 450° C. in an atmosphere containing hydrogen offrom 3 to 100% may also be performed as other means of hydrogenation.

[0122] Subsequently, a second interlayer insulating film 462 made froman inorganic insulating film material or from an organic insulatingmaterial is formed on the first interlayer insulating film 461. Anacrylic resin film having a film thickness of 1.6 μm is formed in thisembodiment, and the material used may have a viscosity from 10 to 1000cp, preferably between 40 to 200 cp. A material in which unevenness isformed on its surface is used.

[0123] In order to prevent mirror reflection, the surface of a pixelelectrode is made uneven by forming a second interlayer insulating filmwhich forms an uneven surface in this embodiment. Further, the pixelelectrode surface can be made to be uneven and have light scatteringcharacteristics, and therefore a convex portion may also be formed in aregion below the pixel electrode. The formation of the convex portioncan be performed by the same photomask as that for forming the TFTs, andtherefore it can be formed without increasing the number of processsteps. Note that the convex portion may also be formed appropriately onthe substrate of the pixel portion region except the wirings and TFTs.In this way, unevenness is formed in the surface of the pixel electrodealong the unevenness formed in the surface of the insulating film whichcovers the convex portion.

[0124] A film having a level surface may also be used as the secondinterlayer insulating film 462. In this case, it is preferable that thesurface be made uneven by an added process such as a known sandblastingprocess or etching process to prevent mirror reflection, and therebyincreasing whiteness by scattering reflected light.

[0125] Wirings 463 to 467 for electrically connecting respectiveimpurity regions are then formed in a driver circuit 506. Note that alamination film of a Ti film having a thickness of 50 nm and an alloyfilm (an alloy of Al and Ti) having a thickness of 500 nm is patternedin order to form the wirings. Of course, it is not limited to thetwo-layer structure, the single-layer structure or the laminationstructure more than three layers may also be acceptable. Further, Al andTi are not limited to the wiring material. For example, Al and Cu areformed on TaN film, and the lamination film forming the Ti film isformed by the patterning and form wiring (FIG. 10).

[0126] Further, a pixel electrode 470, a gate wiring 469, and aconnection electrode 468 are formed in a pixel portion 507. Anelectrical connection is formed with the pixel TFT and the source wiringby the connection electrode 468. Further, the gate wiring 469 forms anelectrical connection with the gate electrode of the pixel TFT. Thepixel electrode 470 forms an electrical connection with the drain region444 of the pixel TFT, and in addition, forms an electrical connectionwith the semiconductor layer 459 which functions as one electrodeforming a storage capacitor. It is preferable to use a material havingsuperior reflectivity, such as a film having Al or Ag as its mainconstituent, or a lamination film of such films, as the pixel electrode470.

[0127] A CMOS circuit composed of a n-channel TFT 501 and a p-channelTFT 502, a driver circuit 506 having an n-channel TFT 503, and the pixelportion 507 having a pixel TFT 504 and a storage capacitor 505 can thusbe formed on the same substrate. The active matrix substrate is thuscompleted.

[0128] The n-channel TFT 501 of the driver circuit 506 has: a channelforming region 437; the low concentration impurity region 436 (GOLDregion) which overlaps with the first conductive layer 428 a thatstructures a portion of the gate electrode; and the high concentrationimpurity region 452 which functions as a source region or a drainregion. The p-channel TFT 502, which forms the CMOS circuit with then-channel TFT 501 and the electrode 466 by an electrical connection has:a channel forming region 455; the low concentration impurity region 454;and the impurity region 453 in which the impurity elements impartingn-type and p-type are introduced. Further, the n-channel TFT 503 has: achannel forming region 443; the low concentration impurity region 442(GOLD region) which overlaps with the first conductive layer 430 a thatstructures a portion of the gate electrode; and the high concentrationimpurity region 441 which functions as a source region or a drainregion.

[0129] The pixel TFT 504 of the pixel portion has: a channel formingregion 446; the low concentration impurity region 445 (LDD region)formed on the outside of the gate electrode; and the high concentrationimpurity region 458 which functions as a source region or a drainregion. Further, an impurity element which imparts n-type and animpurity element which imparts p-type are added to the semiconductorlayer which functions as one electrode of the storage capacitor 505. Thestorage capacitor 505 comprises an electrode (lamination of 432 a and432 b) and the semiconductor layer, with the insulating film 416functioning as a dielectric.

[0130] Edge portions of the pixel electrodes are disposed so as tooverlap with source wirings such that gaps between the pixel electrodesshield the light, without using a black matrix, with the pixel structureof this embodiment.

[0131] An upper surface diagram of the pixel portion of the activematrix substrate manufactured in this embodiment is shown in FIG. 11.Note that the same reference symbols are used for portions correspondingto those in FIGS. 8 to 11. A chain line A-A′ in FIG. 10 corresponds to across sectional diagram cut along a chain line A-A′ within FIG. 11.Further, a chain line B-B′ in FIG. 10 corresponds to a cross sectionaldiagram cut along a chain line B-B′ within FIG. 11.

[0132] Embodiment 6

[0133] A process of manufacturing a reflection type liquid crystaldisplay device from the active matrix substrate manufactured inEmbodiment 5 is explained below in this embodiment. FIG. 12 is used inthe explanation.

[0134] An active matrix substrate in the state of FIG. 10 is firstobtained in accordance with Embodiment 5, an orientation film 567 isthen formed on at least the pixel electrode 470 on the active matrixsubstrate of FIG. 10, and a rubbing process is performed. Note that,before forming the orientation film 567 in this embodiment, columnarspacer 572 is formed in desired positions by patterning an organic resinfilm, such as an acrylic resin film and the like, in order to maintain agap between substrates. Further, spherical spacers may also bedistributed over the entire surface of the substrate as a substitute forthe columnar spacers.

[0135] An opposing substrate 569 is prepared next. Coloring layers 570and 571, and a leveling film 573 are then formed on the opposingsubstrate 569. The red coloring layer 570 and a blue coloring layer 571are overlapped to form a light shielding portion. Furthermore, the lightshielding portion may also be formed by overlapping a portion of the redcoloring layer with a green coloring layer.

[0136] The substrate shown in Embodiment 5 is used in this embodiment.Therefore, with the top view of the pixel portion of Embodiment 5 shownin FIG. 11, it is necessary that, at least, the gap between the gatewiring 469 and the pixel electrode 470, the gap between the gate wiring469 and the connection electrode 468, and the gap between the connectionelectrode 468 and the pixel electrode 470 be shielded from light. Eachof the coloring layers are arranged such that the light shieldingportions made from the lamination of the coloring layers are formed inpositions that must be shielded from light, and then are joined to theopposing substrate.

[0137] It is thus made possible to reduce the number of process steps byperforming light shielding of the respective gaps between the pixels byusing the light shielding portions, composed of the laminations of thecoloring layers, without forming a light shielding layer such as a blackmask and the like.

[0138] An opposing electrode 576 made from a transparent conductive filmis formed on the leveling film 573 over at least the pixel portion, anorientation film 574 is formed over the entire surface of the opposingsubstrate, and a rubbing process is performed.

[0139] The active matrix substrate on which the pixel portion and thedriver circuit are formed, and the opposing substrate are then joined bya sealing material 568. A filler is mixed into the sealing material 568,and the two substrates are joined while maintaining a uniform gap inaccordance with the filler and the columnar spacers. A liquid crystalmaterial 575 is then injected between both substrates, and thesubstrates are completely sealed by using a sealant (not shown in thefigure). A known liquid crystal material may be used for the liquidcrystal material 575. The reflection type liquid crystal display deviceshown in FIG. 12 is thus completed. The active matrix substrate or theopposing substrate is then cut into a desired shape if necessary. Inaddition, a polarizing plate (not shown in the figure) is attached toonly the opposing substrate. An FPC is then attached using a knowntechnique.

[0140] Liquid crystal display device made by above-mentioned method hasTFT manufactured by using the semiconductor film thoroughly annealedbecause the laser beam with a very excellent uniformity of the energydistribution is irradiated. It is possible to become the one with enoughoperation characteristic and reliability of the above-mentioned liquidcrystal display device. Such a liquid crystal display can be used as adisplay portion in various kinds of electronic equipment.

[0141] Note that it is possible to freely combine this embodiment withEmbodiments 1 to 5.

[0142] Embodiment 7

[0143] In this embodiment, an example of manufacturing the lightemitting device by using a manufacturing method of TFT that is used forforming an active matrix substrate. In this specification, the lightemitting device is the general term for the display panel enclosed alight emitting element formed on the substrate between the aforesaidsubstrate and the cover member, and to the aforesaid display moduleequipped TFT with the aforesaid display panel. Incidentally, the lightemitting element has a layer including a compound in which anelectroluminescence can be obtained by applying an electric field (alight emitting layer), an anode, and a cathode. Meanwhile, theelectroluminescence in organic compound includes the light emission(fluorescence) upon returning from the singlet-excited state to theground state and the light emission (phosphorescence) upon returningfrom the triplet-excited state to the ground state, including any orboth of light emission.

[0144] In this specification, all layers formed between the anode andthe cathode in the light emitting element are defined as the organiclight emitting layer. The light emitting layer, the hole injectionlayer, the electron injection layer, the hole transportation layer, andthe electron transportation layer, etc. are concretely included in theorganic light emitting layer. The light emitting element basically hasthe structure that the anode layer, the light emitting layer, and thecathode layer are sequentially laminated. In addition to this structure,the light emitting element may also has a structure that the anodelayer, the hole injection layer, the light emitting layer, and thecathode layer are sequentially laminated or a structure that the anodelayer, the hole injection layer, the light emitting layer, the holetransportation layer, and the cathode layer etc. are sequentiallylaminated.

[0145]FIG. 13 is a sectional view of a light emitting device of thisembodiment. In FIG. 13, the switching TFT 603 provided on the substrate700 is formed by using the n-channel TFT 503 of FIG. 10. Consequently,concerning the explanation of the structure, it is satisfactory to referthe explanation on the n-channel TFT 503.

[0146] Incidentally, although this example is of a double gate structureformed with two channel regions, it is possible to use a single gatestructure formed with one channel region or a triple gate structureformed with three.

[0147] The driver circuit provided on the substrate 700 is formed byusing the CMOS circuit of FIG. 10. Consequently, concerning theexplanation of the structure, it is satisfactory to refer theexplanation on the n-channel TFT 601 and p-channel TFT 602.Incidentally, although this embodiment is of a single gate structure, itis possible to use a double gate structure or a triple gate structure.

[0148] Meanwhile, the wirings 701, 703 serve as source wirings of theCMOS circuit while the wiring 702 as a drain wiring. Meanwhile, a wiring704 serves as a wiring to electrically connect between the source wiring708 and the source region of the switching TFT while the wiring 705serves as a wiring to electrically connect between the drain wiring 709and the drain region of the switching TFT.

[0149] Incidentally, a current control TFT 604 is formed by using thep-channel TFT 502 of FIG. 10. Consequently, concerning the explanationof the structure, it is satisfactory to refer to the explanation on thep-channel TFT 502. Incidentally, although this embodiment is of a singlegate structure, it is possible to use a double gate structure or atriple gate structure.

[0150] Meanwhile, the wiring 706 is a source wiring of the currentcontrol TFT (corresponding to a current supply line) while the wiring707 is an electrode to be electrically connected to the pixel electrode711.

[0151] Meanwhile, reference numeral 711 is a pixel electrode (anode of alight-emitting element) formed by a transparent conductive film. As thetransparent conductive film can be used a compound of indium oxide andtin oxide, a compound of indium oxide and zinc oxide, zinc oxide, tinoxide or indium oxide, or otherwise may be used a transparent conductivefilm as above added with gallium. The pixel electrode 711 is formed on aplanar interlayer insulating film 710 prior to forming the wirings. Inthis embodiment, it is very important to planarize the step due to theTFT by using a resin planarizing film 710. A light-emitting layer to beformed later, because being extremely small in thickness, possiblycauses poor light emission due to the presence of a step. Accordingly,it is desired to provide planarization prior to forming a pixelelectrode so that a light-emitting layer can be formed as planar aspossible.

[0152] After forming the wirings 701 to 707, a bank 712 is formed asshown in FIG. 13. The bank 712 may be formed by patterning an insulatingfilm or organic resin film containing silicon having 100 to 400 nm.

[0153] Incidentally, because the bank 712 is an insulating film, cautionmust be paid to element electrostatic breakdown during deposition. Inthis embodiment added is a carbon particle or metal particle to aninsulating film as a material for the bank 712, thereby reducingresistivity and suppressing occurrence of static electricity. In such acase, the addition amount of carbon or metal particle may be adjusted toprovide a resistivity of 1×10⁶ to 1×10¹² Ωm (preferably 1×10⁸ to 1×10¹⁰Ωm).

[0154] A light emitting layer 713 is formed on the pixel electrode 711.Incidentally, although FIG. 13 shows only one pixel, this embodimentseparately forms the light-emitting layer correspondingly to therespective colors of R (red), G (green) and B (blue). Meanwhile, in thisembodiment is formed a low molecular weight organic light emittingmaterial by the deposition process. Specifically, this is a laminationstructure having a copper phthalocyanine (CuPc) film provided in athickness of 20 nm as a hole injecting layer and a tris-8-qyuinolinolatoaluminum complex (Alq₃) film provided thereon in a thickness of 70 nm asa light-emitting layer. The color of emission light can be controlled byadding a fluorescent pigment, such as quinacridone, perylene or DCM1, toAlq₃.

[0155] However, the foregoing example is an example of organic lightemitting material to be used for a light-emitting layer and notnecessarily limited to this. It is satisfactory to form a light-emittinglayer (layer for light emission and carrier movement therefore) byfreely combining a light-emitting layer, a charge transporting layer andan electron injecting layer. For example, although in this embodimentwas shown the example in which a low molecular weight organic lightemitting material is used for a light-emitting layer, it is possible touse an intermediate organic light emitting material and a high molecularweight organic light emitting material. Furthermore, an organiclight-emitting material, having no sublimation property but havingmolecules in the number of 20 or less or chained molecules having alength of 10 μm or less, is provided as a intermediate molecular organiclight emitting material. For an example of using the high molecularweight organic light emitting material, a polythiophene (PEDOT) filmwith a thickness of 20 nm is formed by the spin coating method as a holeinjection layer and the lamination structure installingparaphenylenvinylene (PPV) of about 100 nm on it as a light emittinglayer may be good. The luminescence wave length can be selected from redto blue by using the π-conjugated type polymer of PPV. Meanwhile, it ispossible to use an inorganic material such as silicon carbide for anelectron transporting layer or charge injecting layer. These organiclight emitting materials or inorganic materials can be a known material.

[0156] Next, a cathode 714 of a conductive film is provided on thelight-emitting layer 713. In this embodiment, as the conductive film isused an alloy film of aluminum and lithium. Of course, a known MgAg film(alloy film of magnesium and silver) may be used. As the cathodematerial may be used a conductive film of an element belonging to theperiodic-table group 1 or 2, or a conductive film added with such anelement.

[0157] A light-emitting element 715 is completed at a time having formedup to the cathode 714. Incidentally, the light-emitting element 715herein refers to a diode formed with a pixel electrode (anode) 711, alight-emitting layer 713 and a cathode 714.

[0158] It is effective to provide a passivation film 716 in such amanner to completely cover the light-emitting element 715. Thepassivation film 716 is formed by an insulating film including a carbonfilm, a silicon nitride film or a silicon oxynitride film, and used isan insulating film in a single layer or a combined lamination.

[0159] In such a case, it is preferred to use a film favorable incoverage as a passivation film. It is effective to use a carbon film,particularly DLC (diamond-like carbon) film. The DLC film, capable ofbeing deposited in a temperature range not more than 100° C. from roomtemperature, can be easily deposited over the light-emitting layer 713low in heat resistance. Meanwhile, the DLC film, having a high blockingeffect to oxygen, can suppress the light-emitting layer 713 fromoxidizing. Consequently, the problem of oxidation can be prevented inthe light-emitting layer 713 during the following sealing process.

[0160] Furthermore, a sealing member 717 is provided on the passivationfilm 716 so as to bond a cover member 718. For the sealing member 717used may be an ultraviolet curable resin. It is effective to providetherein a substance having a hygroscopic effect or an antioxidanteffect. Meanwhile, in this embodiment, for the cover member 718 used isa glass substrate, quartz substrate or plastic substrate (including aplastic film) having carbon films (preferably diamond-like carbon films)formed on the both surfaces thereof. In addition to the carbon film, thealuminum film (such as AlON, AlN, and AlO), SiN and the like are used.

[0161] Thus, completed is a light emitting device having a structure asshown in FIG. 13. Incidentally, it is effective to continuously carryout, without release to the air, the process to form a passivation film716 after forming a bank 712 by using a deposition apparatus of amulti-chamber scheme (or in-line scheme). In addition, with furtherdevelopment it is possible to continuously carry out the process up tobonding a cover member 718, without release to the air.

[0162] In this manner, n-channel TFTs 601 and 602, a switching TFT(n-channel TFT) 603 and a current control TFT (p-channel TFT) 604 areformed on the substrate 700.

[0163] Furthermore, as was explained using FIG. 13, by providing animpurity region overlapped with the gate electrode through an insulatingfilm, it is possible to form an n-channel TFT resistive to thedeterioration resulting from hot-carrier effect. Consequently, a lightemitting device with high reliability can be realized.

[0164] Meanwhile, this embodiment shows only the configuration of thepixel portion and driver circuit. However, according to themanufacturing process in this embodiment, besides these, it is possibleto form on the same insulating member such logic circuits as a signaldivision circuit, a D/A converter, an operation amplifier, aγ-correction circuit or the like. Furthermore, a memory ormicroprocessor can be formed.

[0165] The light emitting device formed by the above-mentioned methodhas TFT formed by using the semiconductor film thoroughly annealed,because it is irradiated the laser beam that has a very excellentuniform energy distribution. Therefore, the above-mentioned lightemitting device is obtained enough operation characteristic andreliability. Such a light emitting device can be used as displayportions of various electronic equipments.

[0166] Incidentally, this embodiment can be freely combined withEmbodiments 1 to 5.

[0167] Embodiment 8

[0168] In this embodiment, an example of performing crystallization of asemiconductor film by using an optical system will be described withreference to FIG. 1 and FIG. 17.

[0169] In this embodiment, a silicon oxynitride film (compositionalratio: Si=32%, O=59%, N=7%, H=2%) with a thickness of 400 nm is formedon a glass substrate as a base film by plasma CVD method. Subsequently,an amorphous silicon film with a thickness of 150 nm is formed on thebase film as a semiconductor film by plasma CVD method. Hydrogencontained in the semiconductor film is released by performing heattreatment at 500° C. for three hour. Then crystallization of thesemiconductor film is performed by a laser annealing method. Thecrystallization of the semiconductor film is performed under thecondition of the laser annealing method that a second harmonic wave ofYVO₄ laser is used as a laser beam, an incident angles φ of the laserbeam relative to a convex lens 103 of an optical system shown in FIG. 1is set to 18° to form a rectangular shape beam, whereby irradiating thesemiconductor film as moving the substrate at a speed of 50 cm/s.

[0170] A seco-etching is performed to the crystalline semiconductor filmthus obtained, and the result of observing the surface of thecrystalline semiconductor film with a SEM (scanning electron microscopy)by one thousand times is shown in FIG. 17. Note that, the seco solutionin the seco-etching is the one made by using K₂Cr₂O₇ for HF:H₂O=2:1 asan additive. FIG. 17 was obtained by relatively scanning the laser beamin the direction indicated by the arrow in figure, and FIG. 17 shows theappearance that crystal grains of large grain size is formed in aperpendicular direction relative to the scanning direction.

[0171] Therefore, since the crystal grains of large grain size areformed in the semiconductor film wherein crystallization is conducted byusing the present invention, when TFT is fabricated by using thesemiconductor film, the number of crystal boundaries that may becontained in a channel forming region can be reduced. Further, since anindividual crystal grain has the crystallinity such that it can beregarded substantially single crystal, the high mobility (field effectmobility) equal to or more than that of a transistor using a singlecrystal semiconductor can be obtained.

[0172] In addition, since the formed crystal grains become complete inone direction, the number of crossing across the crystal grain boundaryby a carrier can be remarkably reduced. Therefore, it is possible toreduce variations of an on current value (a value of a drain currentflowing in an on state of a TFT), an off current value (a value of adrain current flowing in an off state of a TFT), a threshold voltage, anS value, and field effect mobility. And electric characteristic isextremely improved.

[0173] Embodiment 9

[0174] Present embodiment will be described an example of conducting acrystallization of a semiconductor film in the different method fromEmbodiment 8 with reference to FIGS. 1 and 18.

[0175] It forms to the amorphous silicon film as a semiconductor film inaccordance with Embodiment 8. Further, by applying a method recorded inJapanese Patent Laid-open No. Hei 7-183540, an aqueous nickel acetatesolution (weight converting concentration 5 ppm, volume 10 ml) isapplied to the surface of the semiconductor film by spin coating toperform heat treatment in the nitrogen atmosphere at 500° C. for onehour and in the nitrogen atmosphere at 550° C. for twelve hour.Subsequently, an improvement of crystallinity of the semiconductor filmis performed by laser annealing method. The improvement of crystallinityof the semiconductor film is performed under the condition of the laserannealing method that a second harmonic wave of YVO₄ laser is used as alaser beam, an incident angles φ of the laser beam relative to a convexlens 103 of an optical system shown in FIG. 1 is set to 18° to form arectangular shape beam, whereby irradiating the semiconductor film asmoving the substrate at a speed of 50 cm/s.

[0176] A seco-etching is performed to the crystalline semiconductor filmthus obtained, and the surface of the crystalline semiconductor film isobserved with the SEM by one thousand times. An observation result isshown in FIG. 18. The observation result in FIG. 18 was obtained byrelatively scanning the laser beam in the direction indicated by thearrow in figure, and FIG. 18 shows the appearance that crystal grains oflarge grain size is formed in a parallel direction relative to thescanning direction. Further, it is characteristics that crystal grainsshown in FIG. 18 has fewer grain boundaries formed in the directionwhich intersects to relative scanning direction of laser beam than thatshown in FIG. 17.

[0177] Therefore, since the crystal grains of large grain size areformed in the semiconductor film wherein crystallization is conducted byusing the present invention, when TFT is fabricated by using thesemiconductor film, the number of crystal boundaries that may becontained in a channel forming region can be reduced. Further, since anindividual crystal grain has the crystallinity such that it can beregarded substantially single crystal, the high mobility (field effectmobility) equal to or more than that of a transistor using a singlecrystal semiconductor can be obtained.

[0178] In addition, since the formed crystal grains become complete inone direction, the number of crossing across the crystal grain boundaryby a carrier can be remarkably reduced. Therefore, it is possible toreduce variations of an on current value, an off current value, athreshold voltage, an S value, and field effect mobility. And electriccharacteristic is extremely improved.

[0179] Embodiment 10

[0180] Present embodiment will be described an example of conductingcrystallization of a semiconductor film by using an optical system ofthe present invention and manufacturing TFT by using the semiconductorfilm with reference to FIG. 1, FIG. 19 and FIG. 20.

[0181] In this embodiment, a glass film is used as a substrate 20, and asilicon oxynitride film (compositional ratio: Si=32%, O=27%, N=24%,H=17%) with a thickness of 50 nm, and a silicon oxynitride film(compositional ratio: Si=32%, O=59%, N=7%, H=2%) with a thickness of 100nm are laminated on the glass substrate with plasma CVD method.Subsequently, an amorphous silicon film with a thickness of 150 nm isformed on the base film 21 as a semiconductor film 22 by plasma CVDmethod. A hydrogen contained in the semiconductor film is released byperforming heat treatment at 500° C. for three hour. Then, a secondharmonic wave of YVO₄ laser is used as a laser beam, an incident anglesφ of the laser beam relative to a convex lens 103 of an optical systemshown in FIG. 1 is set to 18° to form a rectangular shape beam, wherebyscanning the semiconductor film as moving the substrate at a speed of 50cm/s (FIG. 19B).

[0182] Subsequently, a first doping processing is conducted. The firstdoping processing is a channel doping that controls a threshold value.The first doping processing is conducted by using B₂H₆ as a materialgas, setting the gas flow rate to 30 sccm, the current density to 0.05A, the acceleration voltage to 60 kV, and the dose to 1×10¹⁴/cm² (FIG.19C).

[0183] Subsequently, patterning is performed to etch a semiconductorfilm 24 in a predetermined shape, and then a silicon oxynitride filmwith a thickness of 115 nm is formed as a gate insulating film 27covering the etched semiconductor film by the plasma CVD method.Subsequently, a TaN film 28 with a thickness of 30 nm and a W film 29with a thickness of 370 nm as conductive films are laminated on the gateinsulating film 27 (FIG. 19D).

[0184] A mask made of resist (not shown) is formed by photolithographyto etch the W film, the TaN film and the gate insulating film.

[0185] Subsequently, the mask made of a resist is removed, a new mask 33is formed so as to conduct the second doping processing therebyintroducing impurity elements which impart n-type to the semiconductorfilm. In this case, conductive layers 30 and 31 are become masks withrespect to the impurity elements imparting n-type respectively and animpurity region 34 is formed in a self-aligning manner. In thisembodiment, the second doping processing is divided into two conditionsto be performed since the film thickness of the semiconductor film isvery thick with 150 nm. In this embodiment, at first, the second dopingprocessing of the first condition is performed by using phosphine (PH₃)as a material gas, and setting a dose to 2×10¹³/cm² and the accelerationvoltage to 90 kV. And then, the second doping processing of the secondcondition is performed by setting the dose to 5×10¹⁴/cm² and theacceleration voltage to 10 kV (FIG. 19E).

[0186] Next, the mask 33 made of a resist is removed, a new mask 35 madeof resist is formed, and the third doping processing is performed. Bythe third doping processing, an impurity element for imparting anconductivity type opposite to the one conductivity type is added to animpurity region 36. The impurity region 36 is formed in thesemiconductor film which become an active layer of the p-channel TFT.The conductive layers 30 and 31 are used as a mask to the impurityelement and the impurity element for imparting a p-type is added so asto form impurity region 36 in a self-aligning manner. In thisembodiment, the third doping processing is also divided into twoconditions to be performed since the film thickness of the semiconductorfilm is very thick with 150 nm. In this embodiment, the third dopingprocessing of the first condition is performed by using diborane (B₂H₆)as a material gas and setting the dose to 2×10¹³/cm², and theacceleration voltage to 90 kV. And then, the third doping processing ofthe second condition is performed by setting the dose to 1×10¹⁵/cm², andthe acceleration voltage to 10 kV (FIG. 19F).

[0187] By the steps until now, the impurity regions 34 and 36 are formedin the respective semiconductor layers.

[0188] Next, the mask 35 made of resist is removed and a siliconoxynitride film with a thickness of 50 nm (compositional ratio:Si=32.8%,O=63.7%, H=3.5%) is formed as a first interlayer insulating film 37 byplasma CVD method.

[0189] Next, a recovery of crystallinity of the semiconductor layers andan activation of the impurity element added to the respectivesemiconductor layers are conducted by the heat treatment. In thisembodiment, the heat treatment is performed in a nitrogen atmosphere at550° C. for four hour by a thermal annealing method using an annealingfurnace (FIG. 19G).

[0190] Next, a second interlayer insulating film 38 made of organicinsulating film materials or inorganic insulator materials are formed ona first interlayer insulating film 37. In this embodiment, a siliconnitride film with a thickness of 50 nm is formed by CVD method and thena silicon oxide film with a thickness of 400 nm is formed.

[0191] Next, a hydrogenation processing can be carried out after theheat treatment. In this embodiment, the heat treatment is performed in anitrogen atmosphere at 410° C. for one hour by using the annealingfurnace.

[0192] Subsequently, a wiring 39 electrically connecting to therespective impurity regions is formed. In this embodiment, a laminationfilm of a Ti film with a thickness of 50 nm, an Al—Si film with athickness of 500 nm, and a Ti film with a thickness of 50 nm ispatterned to form. Of course, it is not limited to a two-layerstructure, but also may be a single-layer structure or laminationstructure of three layers or more. Further, materials for wirings arenot limited to Al and Ti. For example, wirings may be formed by formingAl or Cu on the TaN film and patterning the lamination film on which aTi film is formed (FIG. 19H).

[0193] As described above, an n-channel TFT 51 and a p-channel TFT 52are formed.

[0194] An electric characteristic of the n-channel TFT 51 is shown inFIG. 20A and an electric characteristic of the p-channel TFT 52 is shownin FIG. 20B by measuring the electric characteristics. As themeasurement condition of the electric characteristics, measurement pointis assumed to be two points, the gate voltage (Vg) is set to in therange of −16 to 16 V, and the drain voltage (Vd) is set to 1 V and 5 V,respectively. Moreover, in FIGS. 20A and 20B, drain current (ID) andgate current (ID) are shown in a solid line and the mobility (μFE) isshown in a dotted line.

[0195]FIGS. 20A and 20B show that the electric characteristics of TFTmanufactured by using the present invention is remarkably improved. WhenTFT is manufactured by using the semiconductor film, the number ofcrystal grain boundaries that may be contained in a channel formingregion can be reduced, since a crystal grain of large grain size isformed in the semiconductor film, which is crystallized by using thepresent invention. Furthermore, since the crystal grains are formed inthe same direction, it is possible to reduce the number of crossingacross the grain boundary by carrier remarkably. Therefore, the mobilityis 524 cm²/Vs at the n-channel TFT and the mobility is 205 cm²/Vs at thep-channel TFT. When a semiconductor device is manufactured by using suchTFT, the mobility characteristic and the reliability of thesemiconductor device can be improved.

[0196] Embodiment 11

[0197] In this embodiment, an example of conducting crystallization of asemiconductor film by a different method from in Embodiment 10, andmanufacturing TFT by using the semiconductor film will be described withreference to FIGS. 1, 21A to 21C, 22A to 22B, and 23A to 23B.

[0198] It forms to an amorphous silicon film as a semiconductor film inaccordance with Embodiment 10. Further, by applying a method recorded inJapanese Patent Laid-open No. Hei 7-183540, an aqueous nickel acetatesolution (weight converting concentration 5 ppm, volume 10 ml) isapplied to the surface of the semiconductor film by spin coating therebyforming a metal containing layer 41. Then heat treatment is performed inthe nitrogen atmosphere at 500° C. for one hour and in the nitrogenatmosphere at 550° C. for twelve hour (FIG. 21B). Subsequently, animprovement of crystallinity of the semiconductor film is performed bylaser annealing method. The improvement of crystallinity of thesemiconductor film is performed by the laser annealing method under theconditions that a second harmonic wave of YVO₄ laser is used as a laserbeam, an incident angles φ of the laser beam relative to a convex lens103 of an optical system shown in FIG. 1 is set to 18° to form arectangular shape beam, whereby irradiating the semiconductor film asmoving the substrate at a speed of 20 cm/s or 50 cm/s to improve thecrystallinity of the semiconductor film (FIG. 21C).

[0199] In accordance with the Embodiment 10, a n-channel TFT 51 and ap-channel TFT 52 are formed hereafter. The electric characteristics ofthe n-channel TFT and the p-channel TFT are measured, and then anelectric characteristic of the n-channel TFT 51 manufactured by movingthe substrate at a speed of 20 cm/s is shown in FIG. 22A, an electriccharacteristic of the p-channel TFT 52 manufactured by moving thesubstrate at a speed of 20 cm/s is shown in FIG. 22B, an electriccharacteristic of the n-channel TFT 51 manufactured by moving thesubstrate at a speed of 50 cm/s is shown in FIG. 23A, an electriccharacteristic of the p-channel TFT 52 manufactured by moving thesubstrate at a speed of 50 cm/s is shown in FIG. 23B, respectively, inthe laser annealing step. As the measurement condition of the electriccharacteristics, the measurement point is assumed to be two points, thegate voltage (Vg) is set to in the range of −16 to 16 V, and the drainvoltage (Vd) is set to 1.5 V. Moreover, in FIGS. 22A to 22B and FIGS.23A to 23B, drain current (ID) and gate current (ID) is shown in solidline and the mobility (μFE) is shown in dotted line.

[0200]FIGS. 22A to 22B and FIGS. 23A to 23B show that the electriccharacteristics of TFT manufactured by using the present invention isremarkably improved. When TFT is manufactured by using the semiconductorfilm, the number of crystal grain boundaries that may be contained in achannel forming region can be reduced, since a crystal grain of largegrain size is formed in the semiconductor film which is crystallized byusing the present invention. Furthermore, since the formed crystalgrains become complete in one direction and there are few grainboundaries formed in the direction crossed to the relative scanningdirection of laser light, it is possible to reduce the number ofcrossing across the grain boundary by carrier remarkably. Therefore, itis understood that the mobility is 510 cm²/Vs at the n-channel TFT andthe mobility is 200 cm²/Vs at the p-channel TFT in FIGS. 22A to 22B, andthe mobility is 595 cm²/Vs at the n-channel TFT and the mobility is 199cm²/Vs at the p-channel TFT in FIGS. 23A to 23B, and these mobility isvery excellent. When a semiconductor device is manufactured by usingsuch TFT, the mobility characteristic and the reliability of thesemiconductor device can be improved.

[0201] Embodiment 12

[0202] In Embodiments 10 and 11, an example in which a TFT ismanufactured by crystallization methods different from each other isshown. In the present Embodiment 12, difference between thecrystallinities is considered from the TFT characteristics.

[0203] TFT (referred to as PG6 hereinafter) is manufactured according toEmbodiment 11 by combination of laser beam and thermal crystallizationusing nickel having catalytic function in the crystallization. FIG. 25shows dependency of drain current-gate voltage characteristic (ID-VG) ofthe TFT (PG6) on channel length. On the other hand, TFT (referred to asLG6 hereinafter) is manufactured by only laser beam irradiationaccording to Embodiment 10. FIG. 26 shows dependency of ID-VGcharacteristic of the TFT (LG6) on channel length. The channel length is1.5 μm (A) and 2.0 μm (B) and 3.0 μm (C). It is to be noted that ann-channel TFT is used in any case in the present embodiment.

[0204] In FIGS. 25 and 26, the semiconductor film of the sample is 66nm. With this thickness, it is possible to operate in complete depletiontype. As apparent by comparing both the Figures, in the case where thechannel length is as small as 2 μm, conspicuous difference is found inan off region. That is, in the TFT LG6, phenomenon that the draincurrent extraordinarily jumps up is observed. It is confirmed that thisphenomenon depends on the channel dose amount. In any case, it turns outthat as the channel length becomes short, PG6 becomes superior to LG6with respect to withstand voltage between the source and the drain.

[0205] In the complete depletion type having a small thickness of thesemiconductor film, a significant difference is found in the source anddrain withstand voltage. Measurement is conducted to know whethersimilar tendency is observed in a partial depletion type having 150 nmas thickness of the semiconductor film. In FIGS. 27 and 28, ID-VGcharacteristic is shown. The extraordinary jump up of the drain currentin the off region is influenced by drain voltage. As the drain voltageis increased, the extraordinary jump up of the drain current isconspicuous. However, even if the influence is included in theconsideration, it turns out that the PG6 is superior with respect towithstand voltage between the source and the drain. Also, it is judgedin the partial depletion type that PG6 is high in withstand voltagebetween the source and the drain.

[0206] The above result suggests that PG6 is suitable in the case whereelement dimension of TFT is miniaturized into a submicron level.

[0207] Embodiment 13

[0208] Various semiconductor devices (active matrix type liquid crystaldisplay device, active matrix type light emitting device or activematrix type EC display device) can be formed by applying the presentinvention. Specifically, the present invention can be embodied inelectronic equipment of any type in which such an electro-optical deviceis incorporated in a display portion.

[0209] Such electronic equipment is a video camera, a digital camera, aprojector, a head-mounted display (goggle type display), a carnavigation system, a car stereo, a personal computer, a mobileinformation terminal (such as a mobile computer, a mobile telephone oran electronic book etc.) or the like. FIGS. 14A to 14F, 15A to 15D, and16A to 16C show one of its examples.

[0210]FIG. 14A shows a personal computer which includes a main body3001, an image input portion 3002, a display portion 3003, a keyboard3004 and the like. The personal computer of the present invention can becompleted by applying the semiconductor device manufactured by thepresent invention to the display portion 3003.

[0211]FIG. 14B shows a video camera which includes a main body 3101, adisplay portion 3102, a sound input portion 3103, operating switches3104, a battery 3105, an image receiving portion 3106 and the like. Thevideo camera of the present invention can be completed by applying thesemiconductor device manufactured by the present invention to thedisplay portion 3102.

[0212]FIG. 14C shows a mobile computer which includes a main body 3201,a camera portion 3202, an image receiving portion 3203, an operatingswitch 3204, a display portion 3205 and the like. The mobile computer ofthe present invention can be completed by applying the semiconductordevice manufactured by the present invention to the display portion3205.

[0213]FIG. 14D shows a goggle type display which includes a main body3301, a display portion 3302, arm portions 3303 and the like. The goggletype display of the present invention can be completed by applying thesemiconductor device manufactured by the present invention to thedisplay portion 3302.

[0214]FIG. 14E shows a player using a recording medium on which aprogram is recorded (hereinafter referred to as the recording medium),and the player includes a main body 3401, a display portion 3402,speaker portions 3403, a recording medium 3404, operating switches 3405and the like. This player uses a DVD (Digital Versatile Disc), a CD andthe like as the recording medium, and enables a user to enjoy music,movies, games and the Internet. The recording medium of the presentinvention can be completed by applying the semiconductor devicemanufactured by the present invention to the display portion 3402.

[0215]FIG. 14F shows a digital camera which includes a body 3501, adisplay portion 3502, an eyepiece portion 3503, operating switches 3504,an image receiving portion (not shown) and the like. The digital cameraof the present invention can be completed by applying the semiconductordevice manufactured by the present invention to the display portion3502.

[0216]FIG. 15A shows a front type projector which includes a projectiondevice 3601, a screen 3602 and the like. The front type projector can becompleted by applying a liquid crystal display device 3808 whichconstitutes a part of the projection device 3601 and other drivercircuits.

[0217]FIG. 15B shows a rear type projector which includes a main body3701, a projection device 3702, a mirror 3703, a screen 3704 and thelike. The rear type projector can be completed by applying the liquidcrystal display device 3808 which constitutes a part of the projectiondevice 3702 and other driver circuits.

[0218]FIG. 15C shows one example of the structure of each of theprojection devices 3601 and 3702 which are respectively shown in FIGS.15A and 15B. Each of the projection devices 3601 and 3702 is made of alight source optical system 3801, mirrors 3802 and 3804 to 3806, adichroic mirror 3803, a prism 3807, a liquid crystal display device3808, a phase difference plate 3809 and a projection optical system3810. The projection optical system 3810 is made of an optical systemincluding a projection lens. Present embodiment is an example of athree-plate type, but it is not limited to this example and may also beof a single-plate type. In addition, those who embody the invention mayappropriately dispose an optical system such as an optical lens, a filmhaving a polarization function, a film for adjusting phase difference,an IR film or the like in the path indicated by arrows in FIG. 15C.

[0219]FIG. 15D is a view showing one example of the structure of thelight source optical system 3801 shown in FIG. 15C. In this embodiment,the light source optical system 3801 is made of a reflector 3811, alight source 3812, lens arrays 3813 and 3814, a polarizing conversionelement 3815 and a condenser lens 3816. Incidentally, the light sourceoptical system shown in FIG. 15D is one example, and the invention isnot particularly limited to the shown construction. For example, thosewhose embody the invention may appropriately dispose an optical systemsuch as an optical lens, a film having a polarization function, a filmfor adjusting phase difference, an IR film or the like.

[0220] The projector shown in FIGS. 15A to 15D is of the type using atransparent type of electro-optical device, but there is not shown anexample in which the invention is applied to a reflection type ofelectro-optical device and a light emitting device.

[0221]FIG. 16A shows a mobile telephone which includes a main body 3901,a sound output portion 3902, a sound input portion 3903, a displayportion 3904, operating switches 3905, an antenna 3906 and the like. Themobile telephone of the present invention can be completed by applyingthe semiconductor device manufactured by the present invention to thedisplay portion 3904.

[0222]FIG. 16B shows a mobile book (electronic book) which includes amain body 4001, display portions 4002 and 4003, a storage medium 4004,operating switches 4005, an antenna 4006 and the like. The mobile bookof the present invention can be completed by applying the semiconductordevice manufactured by the present invention to the display portions4002 and 4003.

[0223]FIG. 16C shows a display which includes a main body 4101, asupport base 4102, a display portion 4103 and the like. The display ofthe present invention can be completed by applying the semiconductordevice manufactured by the present invention to the display portion4103. The invention is particularly advantageous to a large-screendisplay, and is advantageous to a display having a diagonal size of 10inches or more (particularly, 30 inches or more).

[0224] As is apparent from the foregoing description, the range ofapplications of the invention is extremely wide, and the invention canbe applied to any category of electronic apparatus. Electronic apparatusaccording to the invention can be realized by using a construction madeof a combination of arbitrary ones of Embodiments 1 to 6 and 8 to 11 orEmbodiments 1 to 5 and 7 to 11.

[0225] Embodiment 14

[0226] In the present Embodiment, an example in which a linear beam isformed using a diffractive optics (diffraction grating) instead of theconvex lens used in Embodiment 1 will be described below with referenceto FIG. 24.

[0227] In FIG. 24, a laser 401, a mirror 402, a diffractive optics 403,a linear beam 406, a non-irradiated body 104 and a glass substrate 105are depicted. Moreover, the reference numerals 107, 108 and 109 denotethe directions in which the substrate is moved. When the laser beamemitted from the laser 401 is incident into the diffractive optics 403via the mirror 402, the linear beam 406 can be formed on the irradiationsurface or in its neighborhood. The shape of the linear beam may beformed by appropriately designing the diffractive optics. Moreover, ifthe linear beam is slantly incident into the irradiation surface, theinterference can be prevented.

[0228] It should be noted that a beam expander is set between the laser401 and the mirror 402, or between the mirror 402 and the diffractiveoptics 403, and maybe expanded into the desired sizes in both of thelonger direction and the shorter direction, respectively. Moreover, themirror may not be set, or a plurality of mirrors may be set.

[0229] Then, while the linear beam formed in this way irradiates, it canirradiate the desired region or whole area on the irradiated body 104 bybeing relatively moved with respect to the irradiated body 104, forexample, in the direction indicated with the reference numeral 107 orthe directions indicated with the reference numerals 108, 109.

[0230] Since in the present invention, the optical system for formingthe linear beam has a very simple configuration, it is easy to make aplurality of laser beams linear beams having the same shape on theirradiation surface. Therefore, since the same annealing is carried outin any region where any linear beam irradiates, the whole surface of theirradiated body reaches to have a uniform physical property and thethroughput is enhanced. It should be noted that in Embodiments 2-4, asin the present Embodiment, the diffractive optics could be used insteadof the convex lens.

[0231] It should be noted that the optical system of the presentEmbodiment could be freely combined with Embodiments 5 through 7.

[0232] The fundamental significances indicated as follows can beobtained by employing a configuration of the present invention:

[0233] (a) Since it is a very simplified configuration, the opticaladjustment is easy and the device becomes compact in size. Similarly inthe case where a plurality of lasers of the same kind or a plurality oflasers of different kinds are used, the optical adjustment is easy, andthe device becomes compact in size.

[0234] (b) Since being slantly incident with respect to a plurality oflasers, the return beam can be prevented, and it becomes a simplerconfiguration.

[0235] (c) Even in the case where the irradiation of laser is carriedout using a plurality of laser beams, since the optical system issimplified, it is capable of easily making the same shapes of the alllaser beams. Therefore, uniform annealing can be carried out to theirradiated body. This is particularly effective in the case where asubstrate has a large area.

[0236] (d) It greatly simplifies synthesis of a plurality of laserbeams. Therefore, even if it is a laser having a lower output, it issufficiently applicable by employing a plurality of these.

[0237] (e) The throughput is capable of being enhanced.

[0238] (f) While satisfying these advantages described above, stillmore, the enhancement of the operating property and reliability of asemiconductor device can be realized in a semiconductor devicerepresented by an active matrix type crystal display device.Furthermore, the reduction of the manufacturing cost of thesemiconductor device can be realized.

What is claimed is:
 1. A laser irradiation device comprising: a laser;and a convex lens, wherein said convex lens is slantly set with respectto a laser beam emitted from said laser.
 2. A laser irradiation devicecomprising: a laser; and a convex lens, wherein said convex lens isslantly set with respect to a laser beam emitted from said laser, and anirradiated surface is set so that a laser beam traveled via said convexlens is slantly incident with respect to said irradiation surface.
 3. Alaser irradiation device comprising: a laser; and a convex lens, whereinsaid convex lens is slantly set with respect to a laser beam emittedfrom said laser, an irradiated surface is set so that a laser beamtraveled via said convex lens is slantly incident with respect to saidirradiation surface, and a shape of said laser beam is deformed throughsaid convex lens so that said shape of said laser beam is in a linearshape on an irradiated surface.
 4. A laser irradiation devicecomprising: a laser; and a convex lens, wherein said convex lens isslantly set with respect to a laser beam emitted from said laser, anirradiated surface is set so that a laser beam traveled via said convexlens is slantly incident with respect to said irradiation surface, and ashape of said laser beam is deformed through said convex lens so thatsaid shape of said laser beam is in a linear shape on an irradiatedsurface, wherein a beam length w of said laser beam incident into anirradiated body set over a substrate, and thickness d of said substrate,and an incident angle θ of said laser beam at which angle said laserbeam is incident with respect to said irradiated body satisfy thefollowing expression: θ≧arc tan(w/(2×d))
 5. A device according to claim1, wherein said convex lens is an aspherical lens.
 6. A device accordingto claim 2, wherein said convex lens is an aspherical lens.
 7. A deviceaccording to claim 3, wherein said convex lens is an aspherical lens. 8.A device according to claim 4, wherein said convex lens is an asphericallens.
 9. A laser irradiation device comprising: a laser; and adiffractive optics, wherein said diffractive optics is set so that alaser beam emitted from said laser is slantly incident with respect toan irradiated surface.
 10. A laser irradiation device comprising: alaser; and a diffractive optics, wherein said diffractive optics is setso that a laser beam emitted from said laser is slantly incident withrespect to an irradiated surface, and a shape of said laser beam isdeformed using said diffractive optics so that said shape of said laserbeam is in a linear shape on an irradiated surface.
 11. A laserirradiation device comprising: a laser; and a diffractive optics,wherein said diffractive optics is set so that a laser beam emitted fromsaid laser is slantly incident with respect to an irradiated surface,and a shape of said laser beam is deformed through said diffractiveoptics so that said shape of said laser beam is in a linear shape on anirradiated surface, wherein a beam length w of said laser beam incidentinto an irradiated body set over a substrate, and the thickness d ofsaid substrate, and an incident angle 0 of said laser beam at whichangle said laser beam is incident with respect to said irradiated bodysatisfy the following expression: θ≧arc tan(w/(2×d))
 12. A deviceaccording to claim 1, wherein said laser is a solid state laser, a gaslaser or a metal laser of continuous oscillation or pulse oscillation.13. A device according to claim 2, wherein said laser is a solid statelaser, a gas laser or a metal laser of continuous oscillation or pulseoscillation.
 14. A device according to claim 3, wherein said laser is asolid state laser, a gas laser or a metal laser of continuousoscillation or pulse oscillation.
 15. A device according to claim 4,wherein said laser is a solid state laser, a gas laser or a metal laserof continuous oscillation or pulse oscillation.
 16. A device accordingto claim 9, wherein said laser is a solid state laser, a gas laser or ametal laser of continuous oscillation or pulse oscillation.
 17. A deviceaccording to claim 10, wherein said laser is a solid state laser, a gaslaser or a metal laser of continuous oscillation or pulse oscillation.18. A device according to claim 11, wherein said laser is a solid statelaser, a gas laser or a metal laser of continuous oscillation or pulseoscillation.
 19. A device according to claim 1, wherein said laser isone selected from YAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glasslaser, ruby laser, alexandrite laser, Ti: sapphire laser of continuousoscillation or pulse oscillation.
 20. A device according to claim 2,wherein said laser is one selected from YAG laser, YVO₄ laser, YLFlaser, YAlO₃ laser, glass laser, ruby laser, alexandrite laser, Ti:sapphire laser of continuous oscillation or pulse oscillation.
 21. Adevice according to claim 3, wherein said laser is one selected from YAGlaser, YVO₄ laser, YLF laser, YAlO₃ laser, glass laser, ruby laser,alexandrite laser, Ti: sapphire laser of continuous oscillation or pulseoscillation.
 22. A device according to claim 4, wherein said laser isone selected from YAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glasslaser, ruby laser, alexandrite laser, Ti: sapphire laser of continuousoscillation or pulse oscillation.
 23. A device according to claim 9,wherein said laser is one selected from YAG laser, YVO₄ laser, YLFlaser, YAlO₃ laser, glass laser, ruby laser, alexandrite laser, Ti:sapphire laser of continuous oscillation or pulse oscillation.
 24. Adevice according to claim 10, wherein said laser is one selected fromYAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glass laser, ruby laser,alexandrite laser, Ti: sapphire laser of continuous oscillation or pulseoscillation.
 25. A device according to claim 11, wherein said laser isone selected from YAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glasslaser, ruby laser, alexandrite laser, Ti: sapphire laser of continuousoscillation or pulse oscillation.
 26. A device according to claim 1,wherein said laser is one selected from Ar laser, Kr laser and CO₂laser.
 27. A device according to claim 2, wherein said laser is oneselected from Ar laser, Kr laser and CO₂ laser.
 28. A device accordingto claim 3, wherein said laser is one selected from Ar laser, Kr laserand CO₂ laser.
 29. A device according to claim 4, wherein said laser isone selected from Ar laser, Kr laser and CO₂ laser.
 30. A deviceaccording to claim 9, wherein said laser is one selected from Ar laser,Kr laser and CO₂ laser.
 31. A device according to claim 10, wherein saidlaser is one selected from Ar laser, Kr laser and CO₂ laser.
 32. Adevice according to claim 11, wherein said laser is one selected from Arlaser, Kr laser and CO₂ laser.
 33. A device according to claim 1,wherein said laser is one selected from helium-cadmium laser, coppervapor laser and gold vapor laser of continuous oscillation or pulseoscillation.
 34. A device according to claim 2, wherein said laser isone selected from helium-cadmium laser, copper vapor laser and goldvapor laser of continuous oscillation or pulse oscillation.
 35. A deviceaccording to claim 3, wherein said laser is one selected fromhelium-cadmium laser, copper vapor laser and gold vapor laser ofcontinuous oscillation or pulse oscillation.
 36. A device according toclaim 4, wherein said laser is one selected from helium-cadmium laser,copper vapor laser and gold vapor laser of continuous oscillation orpulse oscillation.
 37. A device according to claim 9, wherein said laseris one selected from helium-cadmium laser, copper vapor laser and goldvapor laser of continuous oscillation or pulse oscillation.
 38. A deviceaccording to claim 10, wherein said laser is one selected fromhelium-cadmium laser, copper vapor laser and gold vapor laser ofcontinuous oscillation or pulse oscillation.
 39. A device according toclaim 11, wherein said laser is one selected from helium-cadmium laser,copper vapor laser and gold vapor laser of continuous oscillation orpulse oscillation.
 40. A device according to claim 1, wherein said laserbeam is converted into a higher harmonic wave using a non-linear opticalelement.
 41. A device according to claim 2, wherein said laser beam isconverted into a higher harmonic wave using a non-linear opticalelement.
 42. A device according to claim 3, wherein said laser beam isconverted into a higher harmonic wave using a non-linear opticalelement.
 43. A device according to claim 4, wherein said laser beam isconverted into a higher harmonic wave using a non-linear opticalelement.
 44. A device according to claim 9, wherein said laser beam isconverted into a higher harmonic wave using a non-linear opticalelement.
 45. A device according to claim 10, wherein said laser beam isconverted into a higher harmonic wave using a non-linear opticalelement.
 46. A device according to claim 11, wherein said laser beam isconverted into a higher harmonic wave using a non-linear opticalelement.
 47. A device according to claim 4 wherein said incident angle θis Brewster's angle.
 48. A device according to claim 11 wherein saidincident angle θ is Brewster's angle.
 49. A laser irradiation methodcomprising: emitting a laser beam from a laser, making said laser beamslantly incident with respect to a convex lens slantly set with respectto said laser beam, deforming a shape of said laser beam through saidconvex lens so that said shape of said laser beam is in a linear shapeon an irradiated body, and irradiating said linear laser beam to saidirradiated body while said linear laser beam and said irradiated bodyare relatively moved.
 50. A laser irradiation method comprising:emitting a laser beam from a laser, making said laser beam slantlyincident with respect to said convex lens slantly set with respect tosaid laser beam, setting an irradiated surface so that a laser beamtraveled via said convex lens is slantly incident with respect to saidirradiated surface, deforming a shape of said laser beam through saidconvex lens so that said shape of said laser beam is in a linear shapeon said irradiated surface, and irradiating said laser beam in saidlinear shape to said irradiated surface while said laser beam in saidlinear shape and said irradiated surface are relatively moved.
 51. Alaser irradiation method comprising: emitting a laser beam from saidlaser, making said laser beam slantly incident with respect to saidconvex lens slantly set with respect to said laser beam, deforming ashape of said laser beam through said convex lens so that said shape ofsaid laser beam is in a linear shape on an irradiated surface,irradiating said laser beam in said linear shape to said irradiatedsurface while said laser beam in said linear shape and said irradiatedsurface are relatively moved, wherein a beam length w of said laser beamincident into said irradiated surface set over a substrate, andthickness d of said substrate, and an incident angle θ of said laserbeam at which angle said laser beam is incident with respect to saidirradiated surface satisfy the following expression: θ≧arc tan(w/(2×d))52. A method according to claim 49, wherein as said convex lens, anaspherical lens is used.
 53. A method according to claim 50, wherein assaid convex lens, an aspherical lens is used.
 54. A method according toclaim 51, wherein as said convex lens, an aspherical lens is used.
 55. Alaser irradiation method comprising: emitting a laser beam from saidlaser, making said laser beam slantly incident with respect to saiddiffractive optics set so that said laser beam is slantly incident withrespect to an irradiated surface, deforming a shape of said laser beamthrough said diffractive optics so that said shape of said laser beam isin a linear shape on an irradiated surface set so that laser beamtransmitted via said convex lens is slantly incident with respect tosaid irradiated surface, and irradiating said laser beam in said linearshape to said irradiated surface while said laser beam in said linearshape and said irradiated surface are relatively moved.
 56. A laserirradiation method comprising: emitting a laser beam from said laser,making said laser beam incident with respect to said diffractive opticsset so that said laser beam is slantly incident with respect to anirradiated surface, deforming a shape of said laser beam through saiddiffractive optics so that said shape of said laser beam is in a linearshape on an irradiated surface, irradiating said laser beam in saidlinear shape to said irradiated surface while said laser beam in saidlinear shape and said irradiated surface are relatively moved, wherein abeam length w of said laser beam incident into said irradiated surfaceset over a substrate, and thickness d of said substrate, an incidentangle θ of said laser beam at which angle said laser beam is incidentwith respect to said irradiated surface satisfy the followingexpression: θ≧arc tan(w/(2×d))
 57. A method according to claim 49,wherein said laser beam is oscillated from a solid state laser, a gaslaser or a metal laser of continuous oscillation or pulse oscillation.58. A method according to claim 50, wherein said laser beam isoscillated from a solid state laser, a gas laser or a metal laser ofcontinuous oscillation or pulse oscillation.
 59. A method according toclaim 51, wherein said laser beam is oscillated from a solid statelaser, a gas laser or a metal laser of continuous oscillation or pulseoscillation.
 60. A method according to claim 55, wherein said laser beamis oscillated from a solid state laser, a gas laser or a metal laser ofcontinuous oscillation or pulse oscillation.
 61. A method according toclaim 56, wherein said laser beam is oscillated from a solid statelaser, a gas laser or a metal laser of continuous oscillation or pulseoscillation.
 62. A method according to claim 49, wherein said laser beamis oscillated from one selected from YAG laser, YVO₄ laser, YLF laser,YAlO₃ laser, glass laser, ruby laser, alexandrite laser, Ti: sapphirelaser of continuous oscillation or pulse oscillation.
 63. A methodaccording to claim 50, wherein said laser beam is oscillated from oneselected from YAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glasslaser, ruby laser, alexandrite laser, Ti: sapphire laser of continuousoscillation or pulse oscillation.
 64. A method according to claim 51,wherein said laser beam is oscillated from one selected from YAG laser,YVO₄ laser, YLF laser, YAlO₃ laser, glass laser, ruby laser, alexandritelaser, Ti: sapphire laser of continuous oscillation or pulseoscillation.
 65. A method according to claim 55, wherein said laser beamis oscillated from one selected from YAG laser, YVO₄ laser, YLF laser,YAlO₃ laser, glass laser, ruby laser, alexandrite laser, Ti: sapphirelaser of continuous oscillation or pulse oscillation.
 66. A methodaccording to claim 56, wherein said laser beam is oscillated from oneselected from YAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glasslaser, ruby laser, alexandrite laser, Ti: sapphire laser of continuousoscillation or pulse oscillation.
 67. A method according to claim 49,wherein said laser beam is oscillated from one selected from Ar laser,Kr laser and CO₂ laser.
 68. A method according to claim 50, wherein saidlaser beam is oscillated from one selected from Ar laser, Kr laser andCO₂ laser.
 69. A method according to claim 51, wherein said laser beamis oscillated from one selected from Ar laser, Kr laser and CO₂ laser.70. A method according to claim 55, wherein said laser beam isoscillated from one selected from Ar laser, Kr laser and CO₂ laser. 71.A method according to claim 56, wherein said laser beam is oscillatedfrom one selected from Ar laser, Kr laser and CO₂ laser.
 72. A methodaccording to claim 49, wherein said laser beam is oscillated from oneselected from helium-cadmium laser, copper vapor laser and gold vaporlaser of continuous oscillation or pulse oscillation.
 73. A methodaccording to claim 50, wherein said laser beam is oscillated from oneselected from helium-cadmium laser, copper vapor laser and gold vaporlaser of continuous oscillation or pulse oscillation.
 74. A methodaccording to claim 51, wherein said laser beam is oscillated from oneselected from helium-cadmium laser, copper vapor laser and gold vaporlaser of continuous oscillation or pulse oscillation.
 75. A methodaccording to claim 55, wherein said laser beam is oscillated from oneselected from helium-cadmium laser, copper vapor laser and gold vaporlaser of continuous oscillation or pulse oscillation.
 76. A methodaccording to claim 56, wherein said laser beam is oscillated from oneselected from helium-cadmium laser, copper vapor laser and gold vaporlaser of continuous oscillation or pulse oscillation.
 77. A methodaccording to claim 49, wherein said laser beam is converted into ahigher harmonic wave through a non-linear optical element.
 78. A methodaccording to claim 50, wherein said laser beam is converted into ahigher harmonic wave through a non-linear optical element.
 79. A methodaccording to claim 51, wherein said laser beam is converted into ahigher harmonic wave through a non-linear optical element.
 80. A methodaccording to claim 55, wherein said laser beam is converted into ahigher harmonic wave through a non-linear optical element.
 81. A methodaccording to claim 56, wherein said laser beam is converted into ahigher harmonic wave through a non-linear optical element.
 82. A methodof manufacturing a semiconductor device comprising: forming asemiconductor film over a substrate, crystallizing said semiconductorfilm by irradiating a first laser beam thereto while said semiconductorfilm and said first laser beam are relatively moved, adding an impurityelement to said crystallized semiconductor film, and activating saidimpurity element by irradiating a second laser beam to saidsemiconductor film while said impurity added semiconductor film and saidsecond laser beam are relatively moved, wherein a shape of each of saidfirst laser beam and said second laser beam traveled via a convex lensis deformed so that said shape of each of said first laser beam and saidsecond laser beam is in a linear shape in said semiconductor film.
 83. Amethod of manufacturing a semiconductor device comprising: forming asemiconductor film over a substrate, crystallizing said semiconductorfilm by irradiating a first laser beam thereto while said semiconductorfilm and said first laser beam are relatively moved, adding an impurityelement to said crystallized semiconductor film, and activating saidimpurity element by irradiating a second laser beam to saidsemiconductor film while said impurity added semiconductor film and saidsecond laser beam are relatively moved, wherein a shape of each of saidfirst laser beam and said second laser beam traveled via a convex lensis deformed so that said shape of each of said first laser beam and saidsecond laser beam is in a linear shape in said semiconductor film andeach of said first laser beam and said second laser beam traveled viasaid convex lens is slantly incident with respect to said semiconductorfilm.
 84. A method of manufacturing a semiconductor device comprising:forming a semiconductor film over a substrate, crystallizing saidsemiconductor film by irradiating a first laser beam thereto while saidsemiconductor film and said first laser beam are relatively moved,adding an impurity element to said crystallized semiconductor film, andactivating said impurity element by irradiating a second laser beam tosaid semiconductor film while said impurity added semiconductor film andsaid second laser beam are relatively moved, wherein a shape of each ofsaid first laser beam and said second laser beam traveled via a convexlens is deformed so that said shape of each of said first laser beam andsaid second laser beam is in a linear shape in said semiconductor film,and each of said first laser beam and said second laser beam traveledvia said convex lens is slantly incident with respect to saidsemiconductor film, wherein a beam length w of each of said first laserbeam and said second laser beam incident into said semiconductor film,and thickness d of said substrate, and an incident angle 0 of each ofsaid first laser beam and said second laser beam at which angle each ofsaid first laser beam and said second laser beam is incident withrespect to said semiconductor film satisfy the following expression:θ≧arc tan(w/(2×d))
 85. A method according to claim 82, wherein as saidconvex lens, an aspherical lens is used.
 86. A method according to claim83, wherein as said convex lens, an aspherical lens is used.
 87. Amethod according to claim 84, wherein as said convex lens, an asphericallens is used.
 88. A method of manufacturing a semiconductor devicecomprising: forming a semiconductor film over a substrate, crystallizingsaid semiconductor film by irradiating a first laser beam thereto whilesaid semiconductor film and said first laser beam are relatively moved,adding an impurity element to said crystallized semiconductor film, andactivating said impurity element by irradiating a second laser light tosaid semiconductor film while said impurity added semiconductor film andsaid second laser beam are relatively moved, wherein a shape of each ofsaid first laser beam and said second laser beam traveled via adiffractive optics is deformed so that said shape of each of said firstlaser beam and said second laser beam is in a linear shape in saidsemiconductor film.
 89. A method of manufacturing a semiconductor devicecomprising: forming a semiconductor film over a substrate, crystallizingsaid semiconductor film by irradiating a first laser beam thereto whilesaid semiconductor film and said first laser beam are relatively moved,adding an impurity element to said crystallized semiconductor film, andactivating said impurity element by irradiating a second laser beam tosaid semiconductor film while said impurity added semiconductor film andsaid second laser beam are relatively moved, wherein a shape of each ofsaid first laser beam and said second laser beam traveled via adiffractive optics is deformed so that said shape of each of said firstlaser beam and said second laser beam is in a linear shape in saidsemiconductor film and each of said first laser beam and said secondlaser beam traveled via said diffractive optics is slantly incident withrespect to said semiconductor film.
 90. A method of manufacturing asemiconductor device comprising: forming a semiconductor film over asubstrate, crystallizing said semiconductor film by irradiating a firstlaser beam thereto while said semiconductor film and said first laserbeam are relatively moved, adding an impurity element to saidcrystallized semiconductor film, and activating said impurity element byirradiating a second laser beam to said semiconductor film while saidimpurity added semiconductor film and said second laser beam arerelatively moved, wherein a shape of each of said first laser beam andsaid second laser beam traveled via a diffractive optics is deformed sothat said shape of each of said first laser beam and said second laserbeam is in a linear shape in said semiconductor film, each of said firstlaser beam and said second laser beam traveled via said diffractiveoptics is slantly incident with respect to said semiconductor film,wherein a beam length w of said laser beam incident into saidsemiconductor film, and thickness d of said substrate, and an incidentangle θ of each of said first laser beam and said second laser beam atwhich angle each of said first laser beam and said second laser beam isincident with respect to said semiconductor film satisfy the followingexpression: θ≧arc tan(w/(2×d))
 91. A method according to claim 82,wherein said laser beam is oscillated from a solid state laser, a gaslaser or a metal laser of continuous oscillation or pulse oscillation.92. A method according to claim 83, wherein said laser beam isoscillated from a solid state laser, a gas laser or a metal laser ofcontinuous oscillation or pulse oscillation.
 93. A method according toclaim 84, wherein said laser beam is oscillated from a solid statelaser, a gas laser or a metal laser of continuous oscillation or pulseoscillation.
 94. A method according to claim 88, wherein said laser beamis oscillated from a solid state laser, a gas laser or a metal laser ofcontinuous oscillation or pulse oscillation.
 95. A method according toclaim 89, wherein said laser beam is oscillated from a solid statelaser, a gas laser or a metal laser of continuous oscillation or pulseoscillation.
 96. A method according to claim 90, wherein said laser beamis oscillated from a solid state laser, a gas laser or a metal laser ofcontinuous oscillation or pulse oscillation.
 97. A method according toclaim 82, wherein said laser beam is oscillated from one selected fromYAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glass laser, ruby laser,alexandrite laser, Ti: sapphire laser of continuous wave or pulseoscillation.
 98. A method according to claim 83, wherein said laser beamis oscillated from one selected from YAG laser, YVO₄ laser, YLF laser,YAlO₃ laser, glass laser, ruby laser, alexandrite laser, Ti: sapphirelaser of continuous wave or pulse oscillation.
 99. A method according toclaim 84, wherein said laser beam is oscillated from one selected fromYAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glass laser, ruby laser,alexandrite laser, Ti: sapphire laser of continuous wave or pulseoscillation.
 100. A method according to claim 88, wherein said laserbeam is oscillated from one selected from YAG laser, YVO₄ laser, YLFlaser, YAlO₃ laser, glass laser, ruby laser, alexandrite laser, Ti:sapphire laser of continuous wave or pulse oscillation.
 101. A methodaccording to claim 89, wherein said laser beam is oscillated from oneselected from YAG laser, YVO₄ laser, YLF laser, YAlO₃ laser, glasslaser, ruby laser, alexandrite laser, Ti: sapphire laser of continuouswave or pulse oscillation.
 102. A method according to claim 90, whereinsaid laser beam is oscillated from one selected from YAG laser, YVO₄laser, YLF laser, YAlO₃ laser, glass laser, ruby laser, alexandritelaser, Ti: sapphire laser of continuous wave or pulse oscillation. 103.A method according to claim 82, wherein said laser beam is oscillatedfrom one species selected from Ar laser, Kr laser and CO₂ laser.
 104. Amethod according to claim 83, wherein said laser beam is oscillated fromone species selected from Ar laser, Kr laser and CO₂ laser.
 105. Amethod according to claim 84, wherein said laser beam is oscillated fromone species selected from Ar laser, Kr laser and CO₂ laser.
 106. Amethod according to claim 88, wherein said laser beam is oscillated fromone species selected from Ar laser, Kr laser and CO₂ laser.
 107. Amethod according to claim 89, wherein said laser beam is oscillated fromone species selected from Ar laser, Kr laser and CO₂ laser.
 108. Amethod according to claim 90, wherein said laser beam is oscillated fromone species selected from Ar laser, Kr laser and CO₂ laser.
 109. Amethod according to claim 82, wherein said laser beam is oscillated fromone species selected from helium-cadmium laser, copper vapor laser andgold vapor laser of continuous oscillation or pulse oscillation.
 110. Amethod according to claim 83, wherein said laser beam is oscillated fromone species selected from helium-cadmium laser, copper vapor laser andgold vapor laser of continuous oscillation or pulse oscillation.
 111. Amethod according to claim 84, wherein said laser beam is oscillated fromone species selected from helium-cadmium laser, copper vapor laser andgold vapor laser of continuous oscillation or pulse oscillation.
 112. Amethod according to claim 88, wherein said laser beam is oscillated fromone species selected from helium-cadmium laser, copper vapor laser andgold vapor laser of continuous oscillation or pulse oscillation.
 113. Amethod according to claim 89, wherein said laser beam is oscillated fromone species selected from helium-cadmium laser, copper vapor laser andgold vapor laser of continuous oscillation or pulse oscillation.
 114. Amethod according to claim 90, wherein said laser beam is oscillated fromone species selected from helium-cadmium laser, copper vapor laser andgold vapor laser of continuous oscillation or pulse oscillation.
 115. Amethod according to claim 82, wherein said laser beam is converted intoa higher harmonic wave through a non-linear optical element.
 116. Amethod according to claim 83, wherein said laser beam is converted intoa higher harmonic wave through a non-linear optical element.
 117. Amethod according to claim 84, wherein said laser beam is converted intoa higher harmonic wave through a non-linear optical element.
 118. Amethod according to claim 88, wherein said laser beam is converted intoa higher harmonic wave through a non-linear optical element.
 119. Amethod according to claim 89, wherein said laser beam is converted intoa higher harmonic wave through a non-linear optical element.
 120. Amethod according to claim 90, wherein said laser beam is converted intoa higher harmonic wave through a non-linear optical element.
 121. Amethod according to claim 82, wherein said semiconductor film is a filmcontaining silicon.
 122. A method according to claim 83, wherein saidsemiconductor film is a film containing silicon.
 123. A method accordingto claim 84, wherein said semiconductor film is a film containingsilicon.
 124. A method according to claim 88, wherein said semiconductorfilm is a film containing silicon.
 125. A method according to claim 89,wherein said semiconductor film is a film containing silicon.
 126. Amethod according to claim 90, wherein said semiconductor film is a filmcontaining silicon.
 127. A method according to claim 82 wherein saidsemiconductor device is incorporated into one selected from the groupconsisting of a personal computer, a video camera, a mobile computer, agoggle type display, a player using a recording medium, a digitalcamera, a front type projector, a rear type projector, a mobiletelephone, and an electronic book.
 128. A method according to claim 83wherein said semiconductor device is incorporated into one selected fromthe group consisting of a personal computer, a video camera, a mobilecomputer, a goggle type display, a player using a recording medium, adigital camera, a front type projector, a rear type projector, a mobiletelephone, and an electronic book.
 129. A method according to claim 84wherein said semiconductor device is incorporated into one selected fromthe group consisting of a personal computer, a video camera, a mobilecomputer, a goggle type display, a player using a recording medium, adigital camera, a front type projector, a rear type projector, a mobiletelephone, and an electronic book.
 130. A method according to claim 88wherein said semiconductor device is incorporated into one selected fromthe group consisting of a personal computer, a video camera, a mobilecomputer, a goggle type display, a player using a recording medium, adigital camera, a front type projector, a rear type projector, a mobiletelephone, and an electronic book.
 131. A method according to claim 89wherein said semiconductor device is incorporated into one selected fromthe group consisting of a personal computer, a video camera, a mobilecomputer, a goggle type display, a player using a recording medium, adigital camera, a front type projector, a rear type projector, a mobiletelephone, and an electronic book.
 132. A method according to claim 90wherein said semiconductor device is incorporated into one selected fromthe group consisting of a personal computer, a video camera, a mobilecomputer, a goggle type display, a player using a recording medium, adigital camera, a front type projector, a rear type projector, a mobiletelephone, and an electronic book.